diff --git a/frontend/src/components/admin/SkillsCatalogAdmin.jsx b/frontend/src/components/admin/SkillsCatalogAdmin.jsx
index 83cca0a..3225d01 100644
--- a/frontend/src/components/admin/SkillsCatalogAdmin.jsx
+++ b/frontend/src/components/admin/SkillsCatalogAdmin.jsx
@@ -1,6 +1,15 @@
 import React, { useCallback, useEffect, useMemo, useState } from 'react'
 import { useAuth } from '../../context/AuthContext'
 import api from '../../utils/api'
+import {
+  catalogSkillsForSelection,
+  countCatalogSkillsWithoutCategory,
+  countCatalogSkillsWithoutMain,
+  SKILL_CATEGORY_UNASSIGNED_KEY,
+  SKILL_MAIN_UNASSIGNED_KEY,
+  SKILL_UNASSIGNED_CATEGORY_LABEL,
+  SKILL_UNASSIGNED_MAIN_LABEL,
+} from '../../utils/skillCatalogTree'
 
 function bySortThenName(a, b) {
   const sa = a.sort_order != null ? Number(a.sort_order) : 99999
@@ -72,6 +81,7 @@ export default function SkillsCatalogAdmin() {
     status: 'active',
     sort_order: '',
     category_id: '',
+    main_category_id: '',
     karate_relevance: '',
     relevance_level: ''
   })
@@ -84,7 +94,7 @@ export default function SkillsCatalogAdmin() {
   const [editDialog, setEditDialog] = useState(null)
 
   const refreshCategories = useCallback(async (mainId) => {
-    if (mainId == null) {
+    if (mainId == null || mainId === SKILL_MAIN_UNASSIGNED_KEY || typeof mainId !== 'number') {
       setCategories([])
       return
     }
@@ -128,12 +138,19 @@ export default function SkillsCatalogAdmin() {
 
   const sortedCategories = useMemo(() => [...categories].sort(bySortThenName), [categories])
 
-  const skillsInCategory = useMemo(() => {
+  const unassignedMainCount = useMemo(() => countCatalogSkillsWithoutMain(catalog), [catalog])
+
+  const unassignedCategoryCount = useMemo(
+    () => countCatalogSkillsWithoutCategory(catalog, selectedMainId),
+    [catalog, selectedMainId]
+  )
+
+  const skillsInSelection = useMemo(() => {
     if (selectedCategoryId == null) return []
-    return catalog
-      .filter((s) => s.category_id === selectedCategoryId)
-      .sort(bySortThenName)
-  }, [catalog, selectedCategoryId])
+    return [...catalogSkillsForSelection(catalog, selectedMainId, selectedCategoryId)].sort(
+      bySortThenName
+    )
+  }, [catalog, selectedMainId, selectedCategoryId])
 
   useEffect(() => {
     if (!editDialog) return
@@ -179,6 +196,7 @@ export default function SkillsCatalogAdmin() {
       status: s.status || 'active',
       sort_order: s.sort_order ?? '',
       category_id: s.category_id ?? '',
+      main_category_id: s.main_category_id ?? '',
       karate_relevance: s.karate_relevance || '',
       relevance_level:
         s.relevance_level != null && s.relevance_level !== ''
@@ -199,7 +217,7 @@ export default function SkillsCatalogAdmin() {
     try {
       await op()
       await bootstrap()
-      if (selectedMainId) await refreshCategories(selectedMainId)
+      if (typeof selectedMainId === 'number') await refreshCategories(selectedMainId)
       setMessage('Gespeichert.')
       return true
     } catch (e) {
@@ -238,7 +256,7 @@ export default function SkillsCatalogAdmin() {
   }
 
   async function handleSwapSkill(rowId, delta) {
-    const sorted = [...skillsInCategory].sort(bySortThenName)
+    const sorted = [...skillsInSelection].sort(bySortThenName)
     await run(async () => {
       await swapNeighborSortById(sorted, rowId, delta, (id, data) => api.updateSkill(id, data))
     })
@@ -292,16 +310,18 @@ export default function SkillsCatalogAdmin() {
   async function handleSaveSkill(e) {
     e.preventDefault()
     if (!editDialog || editDialog.type !== 'skill') return
-    let cid =
+    const cid =
       skillForm.category_id === '' || skillForm.category_id == null
         ? null
         : Number(skillForm.category_id)
-    const skillRow = catalog.find((s) => s.id === editDialog.id)
-    if (cid == null && skillRow?.category_id) {
-      cid = skillRow.category_id
-    }
+    const mid =
+      cid == null &&
+      skillForm.main_category_id !== '' &&
+      skillForm.main_category_id != null
+        ? Number(skillForm.main_category_id)
+        : null
     const ok = await run(async () => {
-      await api.updateSkill(editDialog.id, {
+      const payload = {
         name: skillForm.name.trim(),
         description: skillForm.description || null,
         category: skillForm.category || null,
@@ -319,16 +339,26 @@ export default function SkillsCatalogAdmin() {
         relevance_level:
           skillForm.relevance_level === '' || skillForm.relevance_level == null
             ? null
-            : Number(skillForm.relevance_level)
-      })
+            : Number(skillForm.relevance_level),
+      }
+      if (cid == null) {
+        payload.main_category_id = mid
+      }
+      await api.updateSkill(editDialog.id, payload)
     })
     if (ok) {
-      if (cid != null && cid !== selectedCategoryId) {
+      if (cid != null) {
         const cat = allCategories.find((c) => c.id === cid)
         if (cat?.main_category_id) {
           setSelectedMainId(cat.main_category_id)
           setSelectedCategoryId(cid)
         }
+      } else if (mid == null) {
+        setSelectedMainId(SKILL_MAIN_UNASSIGNED_KEY)
+        setSelectedCategoryId(SKILL_CATEGORY_UNASSIGNED_KEY)
+      } else {
+        setSelectedMainId(mid)
+        setSelectedCategoryId(SKILL_CATEGORY_UNASSIGNED_KEY)
       }
       closeEditDialog()
     }
@@ -347,7 +377,7 @@ export default function SkillsCatalogAdmin() {
 
   async function handleCreateCategory(e) {
     e.preventDefault()
-    if (selectedMainId == null) return
+    if (selectedMainId == null || selectedMainId === SKILL_MAIN_UNASSIGNED_KEY) return
     const name = newCategoryName.trim()
     if (!name) return
     await run(async () => {
@@ -367,11 +397,17 @@ export default function SkillsCatalogAdmin() {
     const name = newSkillName.trim()
     if (!name) return
     await run(async () => {
-      const created = await api.createSkill({
-        name,
-        category_id: selectedCategoryId,
-        status: 'active'
-      })
+      const body = { name, status: 'active' }
+      if (typeof selectedCategoryId === 'number') {
+        body.category_id = selectedCategoryId
+      } else if (selectedCategoryId === SKILL_CATEGORY_UNASSIGNED_KEY) {
+        body.category_id = null
+        body.main_category_id =
+          typeof selectedMainId === 'number' ? selectedMainId : null
+      } else {
+        return
+      }
+      const created = await api.createSkill(body)
       setNewSkillName('')
       setSelectedSkillId(created.id)
     })
@@ -429,8 +465,9 @@ export default function SkillsCatalogAdmin() {
     <div className="skills-catalog-admin">
       <p className="skills-catalog-admin__intro muted">
         Struktur: <strong>Hauptkategorie</strong> → <strong>Kategorie</strong> →{' '}
-        <strong>Fähigkeit</strong>. Reihenfolge mit Pfeilen; Details über das Stift-Symbol (öffnet
-        ein Fenster — auf dem iPhone nach unten scrollen, falls nötig).
+        <strong>Fähigkeit</strong>. Fähigkeiten ohne Zuordnung finden Sie unter{' '}
+        <strong>{SKILL_UNASSIGNED_MAIN_LABEL}</strong> bzw. <strong>{SKILL_UNASSIGNED_CATEGORY_LABEL}</strong>{' '}
+        (wie in der Auswahlbox). Reihenfolge mit Pfeilen; Details über das Stift-Symbol.
       </p>
 
       {error ? (
@@ -455,6 +492,26 @@ export default function SkillsCatalogAdmin() {
         <section className="skills-catalog-column" aria-label="Hauptkategorien">
           <h3 className="skills-catalog-column__title">Hauptkategorien</h3>
           <ul className="skills-catalog-list">
+            {unassignedMainCount > 0 ? (
+              <li>
+                <div
+                  className={
+                    'skills-catalog-row' +
+                    (selectedMainId === SKILL_MAIN_UNASSIGNED_KEY
+                      ? ' skills-catalog-row--active'
+                      : '')
+                  }
+                >
+                  <button
+                    type="button"
+                    className="skills-catalog-row__label"
+                    onClick={() => selectMain(SKILL_MAIN_UNASSIGNED_KEY)}
+                  >
+                    {SKILL_UNASSIGNED_MAIN_LABEL} ({unassignedMainCount})
+                  </button>
+                </div>
+              </li>
+            ) : null}
             {sortedMains.map((m) => (
               <li key={m.id}>
                 <div
@@ -534,9 +591,57 @@ export default function SkillsCatalogAdmin() {
           <h3 className="skills-catalog-column__title">Kategorien</h3>
           {selectedMainId == null ? (
             <p className="muted skills-catalog-placeholder">Zuerst eine Hauptkategorie wählen.</p>
+          ) : selectedMainId === SKILL_MAIN_UNASSIGNED_KEY ? (
+            <>
+              <ul className="skills-catalog-list">
+                {unassignedCategoryCount > 0 ? (
+                  <li>
+                    <div
+                      className={
+                        'skills-catalog-row' +
+                        (selectedCategoryId === SKILL_CATEGORY_UNASSIGNED_KEY
+                          ? ' skills-catalog-row--active'
+                          : '')
+                      }
+                    >
+                      <button
+                        type="button"
+                        className="skills-catalog-row__label"
+                        onClick={() => selectCategory(SKILL_CATEGORY_UNASSIGNED_KEY)}
+                      >
+                        {SKILL_UNASSIGNED_CATEGORY_LABEL} ({unassignedCategoryCount})
+                      </button>
+                    </div>
+                  </li>
+                ) : null}
+              </ul>
+              <p className="muted skills-catalog-placeholder">
+                Unter {SKILL_UNASSIGNED_MAIN_LABEL} gibt es keine Unterkategorien.
+              </p>
+            </>
           ) : (
             <>
               <ul className="skills-catalog-list">
+                {unassignedCategoryCount > 0 ? (
+                  <li>
+                    <div
+                      className={
+                        'skills-catalog-row' +
+                        (selectedCategoryId === SKILL_CATEGORY_UNASSIGNED_KEY
+                          ? ' skills-catalog-row--active'
+                          : '')
+                      }
+                    >
+                      <button
+                        type="button"
+                        className="skills-catalog-row__label"
+                        onClick={() => selectCategory(SKILL_CATEGORY_UNASSIGNED_KEY)}
+                      >
+                        {SKILL_UNASSIGNED_CATEGORY_LABEL} ({unassignedCategoryCount})
+                      </button>
+                    </div>
+                  </li>
+                ) : null}
                 {sortedCategories.map((c) => (
                   <li key={c.id}>
                     <div
@@ -617,11 +722,13 @@ export default function SkillsCatalogAdmin() {
         <section className="skills-catalog-column" aria-label="Fähigkeiten">
           <h3 className="skills-catalog-column__title">Fähigkeiten</h3>
           {selectedCategoryId == null ? (
-            <p className="muted skills-catalog-placeholder">Zuerst eine Kategorie wählen.</p>
+            <p className="muted skills-catalog-placeholder">
+              Zuerst eine Kategorie oder „{SKILL_UNASSIGNED_CATEGORY_LABEL}“ wählen.
+            </p>
           ) : (
             <>
               <ul className="skills-catalog-list">
-                {skillsInCategory.map((s) => (
+                {skillsInSelection.map((s) => (
                   <li key={s.id}>
                     <div
                       className={
@@ -897,14 +1004,41 @@ export default function SkillsCatalogAdmin() {
                       }))
                     }
                     disabled={busy}
-                    required
                   >
+                    <option value="">{SKILL_UNASSIGNED_CATEGORY_LABEL}</option>
                     {allCategories.map((c) => (
                       <option key={c.id} value={c.id}>
                         {(c.main_category_name ? c.main_category_name + ' · ' : '') + c.name}
                       </option>
                     ))}
                   </select>
+                  {skillForm.category_id === '' || skillForm.category_id == null ? (
+                    <>
+                      <label className="form-label">Hauptkategorie</label>
+                      <select
+                        className="form-input"
+                        value={
+                          skillForm.main_category_id === '' || skillForm.main_category_id == null
+                            ? ''
+                            : String(skillForm.main_category_id)
+                        }
+                        onChange={(e) =>
+                          setSkillForm((f) => ({
+                            ...f,
+                            main_category_id: e.target.value === '' ? '' : e.target.value
+                          }))
+                        }
+                        disabled={busy}
+                      >
+                        <option value="">{SKILL_UNASSIGNED_MAIN_LABEL}</option>
+                        {sortedMains.map((m) => (
+                          <option key={m.id} value={m.id}>
+                            {m.name}
+                          </option>
+                        ))}
+                      </select>
+                    </>
+                  ) : null}
                   <label className="form-label">Legacy-Kurzlabel „category“ (optional)</label>
                   <input
                     className="form-input"
diff --git a/frontend/src/utils/skillCatalogTree.js b/frontend/src/utils/skillCatalogTree.js
index 89e4664..cdf62ed 100644
--- a/frontend/src/utils/skillCatalogTree.js
+++ b/frontend/src/utils/skillCatalogTree.js
@@ -195,3 +195,51 @@ export function defaultExpandedKeysForSkillTree(tree) {
   walk(tree)
   return keys
 }
+
+/** Sentinel für Katalog-Admin: keine Hauptgruppe gewählt. */
+export const SKILL_MAIN_UNASSIGNED_KEY = '__unassigned_main__'
+/** Sentinel für Katalog-Admin: keine Kategorie gewählt. */
+export const SKILL_CATEGORY_UNASSIGNED_KEY = '__unassigned_category__'
+export const SKILL_UNASSIGNED_MAIN_LABEL = 'Ohne Hauptgruppe'
+export const SKILL_UNASSIGNED_CATEGORY_LABEL = 'Ohne Kategorie'
+
+/**
+ * Fähigkeiten für die Admin-Katalog-Auswahl (Hauptgruppe + Kategorie-Slot).
+ * @param {object[]} skills
+ * @param {number|string|null} mainId
+ * @param {number|string|null} categoryId
+ */
+export function catalogSkillsForSelection(skills, mainId, categoryId) {
+  if (!Array.isArray(skills) || categoryId == null) return []
+  if (categoryId === SKILL_CATEGORY_UNASSIGNED_KEY) {
+    if (mainId === SKILL_MAIN_UNASSIGNED_KEY) {
+      return skills.filter((s) => s.main_category_id == null && s.category_id == null)
+    }
+    if (typeof mainId === 'number') {
+      return skills.filter((s) => s.main_category_id === mainId && s.category_id == null)
+    }
+    return []
+  }
+  if (typeof categoryId === 'number') {
+    return skills.filter((s) => s.category_id === categoryId)
+  }
+  return []
+}
+
+/** @param {object[]} skills */
+export function countCatalogSkillsWithoutMain(skills) {
+  if (!Array.isArray(skills)) return 0
+  return skills.filter((s) => s.main_category_id == null).length
+}
+
+/** @param {object[]} skills @param {number|string|null} mainId */
+export function countCatalogSkillsWithoutCategory(skills, mainId) {
+  if (!Array.isArray(skills)) return 0
+  if (mainId === SKILL_MAIN_UNASSIGNED_KEY) {
+    return skills.filter((s) => s.main_category_id == null && s.category_id == null).length
+  }
+  if (typeof mainId === 'number') {
+    return skills.filter((s) => s.main_category_id === mainId && s.category_id == null).length
+  }
+  return 0
+}
diff --git a/frontend/src/utils/skillCatalogTree.test.js b/frontend/src/utils/skillCatalogTree.test.js
index c6477d7..723c3eb 100644
--- a/frontend/src/utils/skillCatalogTree.test.js
+++ b/frontend/src/utils/skillCatalogTree.test.js
@@ -1,9 +1,14 @@
 import { describe, expect, it } from 'vitest'
 import {
   buildSkillCatalogTree,
+  catalogSkillsForSelection,
   collectSkillLeavesFromTree,
+  countCatalogSkillsWithoutCategory,
+  countCatalogSkillsWithoutMain,
   defaultExpandedKeysForSkillTree,
   filterSkillTreeByQuery,
+  SKILL_CATEGORY_UNASSIGNED_KEY,
+  SKILL_MAIN_UNASSIGNED_KEY,
   skillCatalogPathLabel,
 } from './skillCatalogTree.js'
 
@@ -70,4 +75,22 @@ describe('skillCatalogTree', () => {
     const group = kihon?.children?.[0]
     expect(group?.children?.some((s) => s.skillId === 1)).toBe(true)
   })
+
+  it('catalogSkillsForSelection lists unassigned buckets', () => {
+    const skills = [
+      { id: 1, main_category_id: null, category_id: null },
+      { id: 2, main_category_id: 10, category_id: null },
+      { id: 3, main_category_id: 10, category_id: 20 },
+    ]
+    expect(
+      catalogSkillsForSelection(skills, SKILL_MAIN_UNASSIGNED_KEY, SKILL_CATEGORY_UNASSIGNED_KEY).map(
+        (s) => s.id
+      )
+    ).toEqual([1])
+    expect(catalogSkillsForSelection(skills, 10, SKILL_CATEGORY_UNASSIGNED_KEY).map((s) => s.id)).toEqual([
+      2,
+    ])
+    expect(countCatalogSkillsWithoutMain(skills)).toBe(1)
+    expect(countCatalogSkillsWithoutCategory(skills, 10)).toBe(1)
+  })
 })