diff --git a/cypress/support/step_definitions/Moderation.ReportContent/I_confirm_the_reporting_dialog.js b/cypress/support/step_definitions/Moderation.ReportContent/I_confirm_the_reporting_dialog.js
index f14f1bb58..3daee27c7 100644
--- a/cypress/support/step_definitions/Moderation.ReportContent/I_confirm_the_reporting_dialog.js
+++ b/cypress/support/step_definitions/Moderation.ReportContent/I_confirm_the_reporting_dialog.js
@@ -4,7 +4,7 @@ defineStep(/^I confirm the reporting dialog .*:$/, message => {
   cy.contains(message) // wait for element to become visible
   cy.get('.os-modal')
     .within(() => {
-      cy.get('.ds-radio-option-label')
+      cy.get('.report-radio-option')
         .first()
         .click({
           force: true
diff --git a/packages/ui/KATALOG.md b/packages/ui/KATALOG.md
index c43f3f13d..b8c83f7ed 100644
--- a/packages/ui/KATALOG.md
+++ b/packages/ui/KATALOG.md
@@ -13,7 +13,7 @@ Phase 0: Analyse       ██████████ 100% (8/8 Schritte) ✅
 Phase 3: OsButton      ██████████ 100% (133/133 Buttons) ✅
 Phase 4: Tier 1        ██████████ 100% (OsButton, OsIcon, OsSpinner, OsCard) ✅
 Phase 4: Tier A → HTML ██████████ 100% (10 ds-* Wrapper → Plain HTML) ✅
-Phase 4: Tier B        ████████░░  80% (ds-chip→OsBadge✅, ds-tag→OsBadge✅, ds-grid✅, ds-number→OsNumber✅, ds-radio⬜)
+Phase 4: Tier B        ██████████ 100% (ds-chip→OsBadge✅, ds-tag→OsBadge✅, ds-grid✅, ds-number→OsNumber✅, ds-radio→HTML✅)
 Phase 4: Tier B+       ████████░░  75% (ds-table→HTML✅) | Tier 2 begonnen (OsModal✅) | Rest ausstehend (OsInput, OsMenu, OsSelect)
 ```
 
@@ -27,7 +27,7 @@ Phase 4: Tier B+       ████████░░  75% (ds-table→HTML✅)
 | ✅ → Plain HTML | Section, Placeholder, List, ListItem, Container, Heading, Text, Space, Flex, FlexItem, Grid, GridItem, Table (13) |
 | ✅ → OsBadge | Chip (20 Nutzungen → OsBadge), Tag (3 → OsBadge shape="square") |
 | ✅ → OsNumber | Number (5 Nutzungen → OsNumber, CountTo.vue gelöscht, vue-count-to entfernt) |
-| ⬜ → Plain HTML | Radio (1) — Tier B Rest |
+| ✅ → Plain HTML | Radio (1 Datei → native `<input type="radio">` in ReportModal) |
 | ⬜ → UI-Library | Modal, Input, Menu, MenuItem, Select (5) — Tier 2-3 |
 | ⬜ Offen | Form (18 Dateien — HTML oder OsForm?) |
 | ⬜ Nicht in Webapp | Code, CopyField, FormItem, InputError, InputLabel, Page, PageTitle, Logo, Avatar, TableCol, TableHeadCol (11) |
@@ -76,7 +76,7 @@ Phase 4: Tier B+       ████████░░  75% (ds-table→HTML✅)
 | 17 | Input | ⬜ Tier 2 | 23 Dateien → OsInput (gekoppelt mit Form) |
 | 18 | InputError | ⬜ Nicht genutzt | Intern von Input genutzt |
 | 19 | InputLabel | ⬜ Nicht genutzt | Intern von Input genutzt |
-| 20 | Radio | ⬜ Tier B | 1 Datei → native `<input type="radio">` |
+| 20 | Radio | ✅ → HTML | 1 Datei → native `<input type="radio">` + `<fieldset>` (ReportModal) |
 | 21 | Select | ⬜ Tier 4 | 3 Dateien → OsSelect |
 
 ### Layout
@@ -439,7 +439,7 @@ Phase 4: Tier B+       ████████░░  75% (ds-table→HTML✅)
 15. [x] ds-tag (3 Dateien) → OsBadge shape="square" (UI-Library)
 16. [x] ds-grid / ds-grid-item (10 Dateien) → CSS Grid (Plain HTML)
 17. [ ] ds-number (5 Dateien) → `<div class="ds-number">`
-18. [ ] ds-radio (1 Datei) → native `<input type="radio">`
+18. [x] ds-radio (1 Datei) → native `<input type="radio">` + `<fieldset>` (ReportModal) ✅
 
 ### Phase 4: Tier 2-4 — UI-Library
 18. [x] OsModal (h() Render, Focus-Trap, Scroll-Lock, A11y; ConfirmModal + ReportModal nutzen OsModal; DeleteUserModal/DisableModal/ReleaseModal gelöscht) ✅
diff --git a/packages/ui/PROJEKT.md b/packages/ui/PROJEKT.md
index a857ffbcf..52c41d225 100644
--- a/packages/ui/PROJEKT.md
+++ b/packages/ui/PROJEKT.md
@@ -81,10 +81,10 @@ Phase 0: ██████████ 100% (6/6 Aufgaben) ✅
 Phase 1: ██████████ 100% (6/6 Aufgaben) ✅
 Phase 2: ██████████ 100% (26/26 Aufgaben) ✅
 Phase 3: ██████████ 100% (24/24 Aufgaben) ✅ - Webapp-Integration komplett
-Phase 4: ███████░░░  67% (18/27 Aufgaben) - Tier 1 ✅, Tier A ✅, Infra ✅, OsBadge ✅, ds-grid ✅, ds-table→HTML ✅, OsNumber ✅, OsModal ✅ | Tier B (rest), Tier 2-3 ausstehend
+Phase 4: ███████░░░  70% (19/27 Aufgaben) - Tier 1 ✅, Tier A ✅, Infra ✅, OsBadge ✅, ds-grid ✅, ds-table→HTML ✅, OsNumber ✅, OsModal ✅, ds-radio→HTML ✅ | Tier B ✅, Tier 2-3 ausstehend
 Phase 5: ░░░░░░░░░░   0% (0/7 Aufgaben)
 ───────────────────────────────────────
-Gesamt:  ████████░░  83% (80/96 Aufgaben)
+Gesamt:  ████████░░  84% (81/96 Aufgaben)
 ```
 
 ### Katalogisierung (Details in KATALOG.md)
@@ -216,11 +216,20 @@ ds-chip + ds-tag → OsBadge (UI-Library): ✅
 
 ## Aktueller Stand
 
-**Letzte Aktualisierung:** 2026-02-20 (Session 32)
+**Letzte Aktualisierung:** 2026-03-14 (Session 33)
 
-**Aktuelle Phase:** Phase 4 - Tier 1 ✅, Tier A ✅, OsBadge ✅, ds-grid ✅, ds-table→HTML ✅, OsNumber ✅ | Tier B (rest), Tier 2-3 ausstehend
+**Aktuelle Phase:** Phase 4 - Tier 1 ✅, Tier A ✅, Tier B ✅, OsModal ✅ | Tier 2-3 ausstehend
 
-**Zuletzt abgeschlossen (Session 32 - OsNumber: ds-number + CountTo → OsNumber):**
+**Zuletzt abgeschlossen (Session 33 - ds-radio → native HTML):**
+- [x] `<ds-radio>` in ReportModal.vue → native `<fieldset>` + `<input type="radio">` + `<label>`
+- [x] Accessible Radio-Group: `<fieldset>` mit `<legend>` für Screen-Reader
+- [x] CSS: `.report-radio-group`, `.report-radio-option`, `.report-radio-option-label` (in ReportModal `<style>`)
+- [x] ReportModal.spec.js: `.ds-radio-option-label` → `input[type="radio"]` Selektor
+- [x] Cypress E2E: `.ds-radio-option-label` → `input[type="radio"]` Selektor
+- [x] 14/14 Unit-Tests bestanden
+- [x] 0 ds-radio Nutzungen verbleibend
+
+**Zuvor abgeschlossen (Session 32 - OsNumber: ds-number + CountTo → OsNumber):**
 - [x] OsNumber Komponente in packages/ui erstellt (h() Render-Function, requestAnimationFrame Animation)
 - [x] Props: count (required), label (optional), animated (optional, 1500ms ease-out)
 - [x] Animation: requestAnimationFrame-Loop, watch(count) re-animiert von oldVal→newVal
@@ -279,8 +288,7 @@ ds-chip + ds-tag → OsBadge (UI-Library): ✅
 - [x] Test-Fix: Empty.spec.js `attributes().margin` → `classes().toContain('ds-my-xxx-small')`
 - [x] 0 Tier-A `ds-*` Komponenten-Tags verbleibend
 
-**Verbleibende ds-* Komponenten (7 Typen):**
-- Tier B Rest (→ Plain HTML): ds-radio (1)
+**Verbleibende ds-* Komponenten (6 Typen):**
 - Tier C (→ UI-Library): ds-input (23), ds-form (18), ds-modal (7), ds-menu/ds-menu-item (17), ds-select (3)
 
 **Zuvor abgeschlossen (Session 26 - CodeRabbit Review Fixes):**
diff --git a/webapp/components/Modal/ReportModal.spec.js b/webapp/components/Modal/ReportModal.spec.js
index 3b0ded99c..d623a1dec 100644
--- a/webapp/components/Modal/ReportModal.spec.js
+++ b/webapp/components/Modal/ReportModal.spec.js
@@ -162,7 +162,7 @@ describe('ReportModal.vue', () => {
 
       describe('click confirm button', () => {
         beforeEach(async () => {
-          wrapper.find('.ds-radio-option-label').trigger('click')
+          wrapper.find('.report-radio-option').trigger('click')
           await Vue.nextTick()
           wrapper.find('button.confirm').trigger('click')
           await Vue.nextTick()
diff --git a/webapp/components/Modal/ReportModal.vue b/webapp/components/Modal/ReportModal.vue
index 9d4bcb6ab..1d6fef920 100644
--- a/webapp/components/Modal/ReportModal.vue
+++ b/webapp/components/Modal/ReportModal.vue
@@ -9,13 +9,26 @@
     <!-- eslint-disable-next-line vue/no-v-html -->
     <p v-html="message" />
     <div class="ds-mb-small"></div>
-    <ds-radio
-      v-model="form.reasonCategory"
-      :schema="formSchema.reasonCategory"
-      :label="$t('report.reason.category.label')"
-      :options="form.reasonCategoryOptions"
-      labelProp="label"
-    />
+    <fieldset class="report-radio-group" data-test="report-radio-group" role="radiogroup">
+      <legend>{{ $t('report.reason.category.label') }}</legend>
+      <div
+        v-for="(option, index) in form.reasonCategoryOptions"
+        :key="option.value"
+        class="report-radio-option"
+        :class="{ 'report-radio-option-selected': form.reasonCategory === option }"
+        role="radio"
+        :aria-checked="String(form.reasonCategory === option)"
+        :tabindex="form.reasonCategory === option || (!form.reasonCategory && index === 0) ? 0 : -1"
+        @click="selectReasonCategory(option)"
+        @keydown.space.prevent="selectReasonCategory(option)"
+        @keydown.enter.prevent="selectReasonCategory(option)"
+        @keydown.down.prevent="focusRadioOption(index + 1)"
+        @keydown.up.prevent="focusRadioOption(index - 1)"
+      >
+        <span class="report-radio-option-mark" />
+        <span class="report-radio-option-label">{{ option.label }}</span>
+      </div>
+    </fieldset>
     <ds-input
       class="reason-description"
       v-model="form.reasonDescription"
@@ -119,6 +132,18 @@ export default {
         this.$emit('close')
       }, 1000)
     },
+    selectReasonCategory(option) {
+      this.form.reasonCategory = option
+      this.$nextTick(() => {
+        const selected = this.$el.querySelector('.report-radio-option[aria-checked="true"]')
+        if (selected) selected.focus()
+      })
+    },
+    focusRadioOption(index) {
+      const options = this.form.reasonCategoryOptions
+      const wrappedIndex = (index + options.length) % options.length
+      this.selectReasonCategory(options[wrappedIndex])
+    },
     async confirm() {
       const { reasonCategory, reasonDescription } = this.form
       this.loading = true
@@ -174,12 +199,54 @@ export default {
   width: 700px !important;
   max-width: 700px !important;
 }
-.report-modal .ds-radio-option {
-  width: 100% !important;
+.report-modal .report-radio-group {
+  border: none;
+  padding: 0;
+  margin: 0;
 }
-.report-modal .ds-radio-option-label {
-  margin: 5px 20px 5px 5px !important;
-  width: 100% !important;
+.report-modal .report-radio-group legend {
+  font-weight: bold;
+  margin-bottom: $space-xx-small;
+}
+.report-modal .report-radio-option {
+  display: flex;
+  align-items: center;
+  width: 100%;
+  padding: 4px 0;
+  cursor: pointer;
+  user-select: none;
+}
+.report-modal .report-radio-option-mark {
+  display: inline-block;
+  position: relative;
+  width: 16px;
+  height: 16px;
+  min-width: 16px;
+  border: 2px solid $border-color-base;
+  background-color: $background-color-base;
+  border-radius: 50%;
+  margin-right: 8px;
+}
+.report-modal .report-radio-option-mark::before {
+  position: absolute;
+  content: '';
+  top: 50%;
+  left: 50%;
+  transform: translateY(-50%) translateX(-50%) scale(0);
+  opacity: 0;
+  width: 8px;
+  height: 8px;
+  border-radius: 50%;
+  background-color: $text-color-primary;
+  transition: all 0.1s ease-in;
+}
+.report-modal .report-radio-option-selected .report-radio-option-mark::before {
+  opacity: 1;
+  transform: translateY(-50%) translateX(-50%) scale(1);
+}
+.report-modal .report-radio-option-label {
+  cursor: pointer;
+  flex: 1;
 }
 .report-modal .reason-description {
   margin-top: $space-x-small !important;