diff --git a/src/views/account/AccountView.vue b/src/views/account/AccountView.vue
index d810d16..475b0fa 100644
--- a/src/views/account/AccountView.vue
+++ b/src/views/account/AccountView.vue
@@ -276,25 +276,27 @@ async function loadCategories() {
     categories.value = []
   }
 }
-// 현재 구분(수입/지출)에 맞는 분류 + 편집 중 현재 값 보존
-// ===== 분류: 대분류 → 소분류 2단 선택 (긴 드롭다운 스크롤 방지) =====
-const categoryMajor = ref('') // 선택된 대분류 이름
-// 현재 구분의 대분류(부모 없음) 이름 + 편집 중 현재 대분류 보존
-const majorOptions = computed(() => {
-  const names = categories.value
-    .filter((c) => c.type === form.type && c.parentId == null)
-    .map((c) => c.name)
-  if (categoryMajor.value && !names.includes(categoryMajor.value)) names.unshift(categoryMajor.value)
-  return names
-})
-// 선택된 대분류의 소분류 이름 목록 (없으면 대분류 자체가 분류)
-const subOptions = computed(() => {
-  const major = categories.value.find(
-    (c) => c.type === form.type && c.parentId == null && c.name === categoryMajor.value,
-  )
-  if (!major) return []
-  return categories.value.filter((c) => c.parentId === major.id).map((c) => c.name)
-})
+// ===== 분류: 대분류 아코디언 → 소분류 선택 =====
+const categoryMajor = ref('') // 펼쳐진 대분류 이름
+// 현재 구분의 대분류 객체 목록
+const majorOptionsData = computed(() =>
+  categories.value.filter((c) => c.type === form.type && c.parentId == null)
+)
+// 특정 대분류의 소분류 객체 목록
+function subsByMajor(majorId) {
+  return categories.value.filter((c) => c.parentId === majorId)
+}
+// 대분류 클릭: 소분류 있으면 펼침 토글, 없으면 바로 선택
+function onMajorClick(major) {
+  if (categoryMajor.value === major.name) {
+    categoryMajor.value = ''
+    form.category = ''
+  } else {
+    categoryMajor.value = major.name
+    if (!subsByMajor(major.id).length) form.category = major.name
+    else form.category = ''
+  }
+}
 // form.category 로부터 대분류 추론 (편집 진입 시)
 function syncCategoryMajor() {
   const cur = form.category
@@ -310,10 +312,7 @@ function syncCategoryMajor() {
     categoryMajor.value = cur
   }
 }
-// 대분류 변경: 소분류 있으면 소분류 선택 대기 / 없으면 대분류가 곧 분류
-function onMajorChange() {
-  form.category = subOptions.value.length ? '' : categoryMajor.value
-}
+
 // 필터용 전체 분류명 (중복 제거)
 const allCategoryNames = computed(() => [...new Set(categories.value.map((c) => c.name))])
 
@@ -1121,16 +1120,28 @@ onMounted(async () => {
               </template>
 
               <label v-if="form.type === 'INCOME' || form.type === 'EXPENSE'">분류
-                <div v-if="!addingCategory" class="cat-input cascade">
-                  <select v-model="categoryMajor" :disabled="submitting" @change="onMajorChange" title="대분류">
-                    <option value="">대분류 선택</option>
-                    <option v-for="m in majorOptions" :key="m" :value="m">{{ m }}</option>
-                  </select>
-                  <select v-if="subOptions.length" v-model="form.category" :disabled="submitting" title="소분류">
-                    <option value="">소분류 선택</option>
-                    <option v-for="s in subOptions" :key="s" :value="s">{{ s }}</option>
-                  </select>
-                  <button type="button" class="cat-add-btn" :disabled="submitting" @click="startAddCategory">+ 추가</button>
+                <div v-if="!addingCategory" class="cat-accordion">
+                  <div v-for="m in majorOptionsData" :key="m.id" class="acc-major">
+                    <button
+                      type="button" class="acc-major-btn"
+                      :class="{ active: form.category === m.name && !subsByMajor(m.id).length, expanded: categoryMajor === m.name && subsByMajor(m.id).length }"
+                      :disabled="submitting"
+                      @click="onMajorClick(m)"
+                    >
+                      <span class="acc-arrow">{{ subsByMajor(m.id).length ? (categoryMajor === m.name ? '▼' : '▶') : '' }}</span>
+                      {{ m.name }}
+                    </button>
+                    <div v-if="categoryMajor === m.name && subsByMajor(m.id).length" class="acc-subs">
+                      <button
+                        v-for="s in subsByMajor(m.id)" :key="s.id"
+                        type="button" class="acc-sub-btn"
+                        :class="{ active: form.category === s.name }"
+                        :disabled="submitting"
+                        @click="form.category = s.name"
+                      >{{ s.name }}</button>
+                    </div>
+                  </div>
+                  <button type="button" class="cat-add-btn acc-add" :disabled="submitting" @click="startAddCategory">+ 추가</button>
                 </div>
                 <div v-else class="cat-input">
                   <input
@@ -1871,13 +1882,6 @@ button.primary {
   display: flex;
   gap: 0.4rem;
 }
-.cat-input.cascade {
-  flex-wrap: wrap;
-}
-.cat-input.cascade select {
-  flex: 1 1 40%;
-}
-.cat-input select,
 .cat-input input {
   flex: 1;
   min-width: 0;
@@ -1892,6 +1896,79 @@ button.primary {
   border-color: hsla(160, 100%, 37%, 1);
   color: hsla(160, 100%, 37%, 1);
 }
+/* 분류 아코디언 */
+.cat-accordion {
+  border: 1px solid var(--color-border);
+  border-radius: 6px;
+  overflow: hidden;
+  max-height: 200px;
+  overflow-y: auto;
+}
+.acc-major-btn {
+  width: 100%;
+  display: flex;
+  align-items: center;
+  gap: 0.35rem;
+  padding: 0.45rem 0.7rem;
+  border: 0;
+  border-bottom: 1px solid var(--color-border);
+  background: transparent;
+  cursor: pointer;
+  text-align: left;
+  font-size: 0.88rem;
+  color: var(--color-text);
+}
+.acc-major-btn:last-child {
+  border-bottom: 0;
+}
+.acc-major-btn.active,
+.acc-major-btn.expanded {
+  background: var(--color-background-soft);
+  font-weight: 600;
+}
+.acc-major-btn.active {
+  color: hsla(160, 100%, 37%, 1);
+}
+.acc-arrow {
+  font-size: 0.6rem;
+  flex: none;
+  width: 0.9rem;
+  text-align: center;
+  opacity: 0.6;
+}
+.acc-subs {
+  display: flex;
+  flex-direction: column;
+}
+.acc-sub-btn {
+  padding: 0.38rem 0.7rem 0.38rem 2rem;
+  border: 0;
+  border-bottom: 1px solid var(--color-border);
+  background: var(--color-background-soft);
+  cursor: pointer;
+  text-align: left;
+  font-size: 0.84rem;
+  color: var(--color-text);
+}
+.acc-sub-btn:last-child {
+  border-bottom: 0;
+}
+.acc-sub-btn.active {
+  color: hsla(160, 100%, 37%, 1);
+  font-weight: 600;
+}
+.acc-add {
+  display: block;
+  width: 100%;
+  border: 0;
+  border-top: 1px dashed var(--color-border);
+  border-radius: 0;
+  background: transparent;
+  text-align: center;
+  color: var(--color-text);
+  opacity: 0.6;
+  font-size: 0.82rem;
+}
 .tag-field {
   display: flex;
   flex-direction: column;
diff --git a/src/views/account/CategoryView.vue b/src/views/account/CategoryView.vue
index 9ce6cbd..c0ab56f 100644
--- a/src/views/account/CategoryView.vue
+++ b/src/views/account/CategoryView.vue
@@ -66,17 +66,6 @@ async function reload() {
 const majorListEl = ref(null)
 const reorderMode = ref(false)
 
-// ===== 대분류 펼침(아코디언) — 삼각형 누르면 소분류 표시 =====
-const expanded = ref(new Set())
-function toggleExpand(id) {
-  const s = new Set(expanded.value)
-  if (s.has(id)) s.delete(id)
-  else s.add(id)
-  expanded.value = s
-}
-function isExpanded(id) {
-  return expanded.value.has(id)
-}
 let sortables = []
 function destroySortables() {
   sortables.forEach((s) => s.destroy())
@@ -140,16 +129,9 @@ async function addCategory() {
   if (!name) return
   error.value = null
   try {
-    const parentId = newParent.value || null
-    await accountApi.createCategory({ type: activeType.value, name, parentId })
+    await accountApi.createCategory({ type: activeType.value, name, parentId: newParent.value || null })
     newName.value = ''
     await reload()
-    // 소분류를 추가했으면 그 대분류를 펼쳐 바로 보이게
-    if (parentId) {
-      const s = new Set(expanded.value)
-      s.add(Number(parentId))
-      expanded.value = s
-    }
   } catch (e) {
     showError(e, '추가에 실패했습니다.')
   }
@@ -245,18 +227,12 @@ onBeforeUnmount(destroySortables)
         <div class="cat-row major-row">
           <div class="cat-main">
             <span v-show="reorderMode" class="drag-handle major-handle" title="대분류 순서 변경(소분류 함께 이동)">≡</span>
-            <button
-              type="button" class="expand-btn" :class="{ open: isExpanded(g.major.id), empty: !g.children.length }"
-              :title="g.children.length ? (isExpanded(g.major.id) ? '소분류 접기' : '소분류 펼치기') : '소분류 없음'"
-              :disabled="!g.children.length" @click="toggleExpand(g.major.id)"
-            >▶</button>
             <input v-model="g.major.name" class="cat-name" @keyup.enter="saveCategory(g.major)" />
-            <span v-if="g.children.length && !isExpanded(g.major.id)" class="sub-count">{{ g.children.length }}</span>
             <IconBtn icon="check" title="저장" size="sm" @click="saveCategory(g.major)" />
             <IconBtn icon="trash" title="삭제" variant="danger" size="sm" @click="removeCategory(g.major)" />
           </div>
         </div>
-        <ul v-show="isExpanded(g.major.id) || reorderMode" class="sub-list" :data-parent="g.major.id">
+        <ul class="sub-list" :data-parent="g.major.id">
           <li v-for="s in g.children" :key="s.id" :data-id="s.id" class="sub-item cat-row child">
             <div class="cat-main">
               <span v-show="reorderMode" class="drag-handle sub-handle" title="소분류 순서 변경">≡</span>
@@ -468,37 +444,7 @@ button.danger {
 .sub-mark {
   opacity: 0.45;
 }
-/* 대분류 펼침 삼각형 */
-.expand-btn {
-  flex: none;
-  width: 1.4rem;
-  height: 1.4rem;
-  border: 0;
-  background: transparent;
-  color: var(--color-text);
-  font-size: 0.7rem;
-  cursor: pointer;
-  transition: transform 0.15s ease;
-  opacity: 0.7;
-}
-.expand-btn.open {
-  transform: rotate(90deg);
-}
-.expand-btn.empty {
-  opacity: 0.15;
-  cursor: default;
-}
-.sub-count {
-  flex: none;
-  min-width: 1.2rem;
-  text-align: center;
-  font-size: 0.72rem;
-  padding: 0.05rem 0.3rem;
-  border-radius: 999px;
-  background: var(--color-border);
-  color: var(--color-text);
-  opacity: 0.75;
-}
+
 .hint.sm {
   font-size: 0.78rem;
   margin: 0 0 0.75rem;