diff --git a/backend/internal/handler/user.go b/backend/internal/handler/user.go
index cc96811..091ccef 100644
--- a/backend/internal/handler/user.go
+++ b/backend/internal/handler/user.go
@@ -95,3 +95,12 @@ func (h *UserHandler) DeletePlatformAdmin(c *gin.Context) {
 	}
 	response.OK(c, nil)
 }
+
+func (h *UserHandler) DeleteMerchantAccount(c *gin.Context) {
+	id, _ := strconv.ParseUint(c.Param("id"), 10, 64)
+	if err := h.svc.DeleteMerchantAccount(uint(id), middleware.GetUserID(c)); err != nil {
+		response.BadRequest(c, err.Error())
+		return
+	}
+	response.OK(c, nil)
+}
diff --git a/backend/internal/router/router.go b/backend/internal/router/router.go
index a816633..3bf1e89 100644
--- a/backend/internal/router/router.go
+++ b/backend/internal/router/router.go
@@ -195,6 +195,7 @@ func Setup(h *Handlers) *gin.Engine {
 			{
 				admin.GET("/platform/admins", h.User.ListPlatformAdmins)
 				admin.GET("/platform/merchant-accounts", h.User.ListMerchantAccountGroups)
+				admin.DELETE("/platform/merchant-accounts/:id", h.User.DeleteMerchantAccount)
 				admin.POST("/platform/admins", h.User.CreatePlatformAdmin)
 				admin.PATCH("/platform/admins/:id", h.User.UpdatePlatformAdmin)
 				admin.DELETE("/platform/admins/:id", h.User.DeletePlatformAdmin)
diff --git a/backend/internal/service/merchant_test.go b/backend/internal/service/merchant_test.go
index e23259a..ade2a7a 100644
--- a/backend/internal/service/merchant_test.go
+++ b/backend/internal/service/merchant_test.go
@@ -336,3 +336,40 @@ func TestListMerchantAccountGroupsExcludesPlatformAdmins(t *testing.T) {
 		t.Fatalf("unexpected merchant account group: %+v", groups[0])
 	}
 }
+
+func TestDeleteMerchantAccountRemovesAllMemberships(t *testing.T) {
+	db := newServiceTestDB(t)
+	merchantA := model.Merchant{Code: "delete-account-a", Name: "删除账号商户 A", Status: model.MerchantStatusActive}
+	merchantB := model.Merchant{Code: "delete-account-b", Name: "删除账号商户 B", Status: model.MerchantStatusActive}
+	merchantUser := model.User{Username: "delete-merchant-account", PasswordHash: "hash", Role: model.RoleMerchant, Status: 1}
+	platformAdmin := model.User{Username: "delete-account-admin", PasswordHash: "hash", Role: model.RoleAdmin, Status: 1}
+	for _, entity := range []interface{}{&merchantA, &merchantB, &merchantUser, &platformAdmin} {
+		if err := db.Create(entity).Error; err != nil {
+			t.Fatalf("create fixture: %v", err)
+		}
+	}
+	for _, member := range []model.MerchantMember{
+		{MerchantID: merchantA.ID, UserID: merchantUser.ID, Role: model.MemberRoleOperator, Status: 1},
+		{MerchantID: merchantB.ID, UserID: merchantUser.ID, Role: "support", Status: 1},
+	} {
+		if err := db.Create(&member).Error; err != nil {
+			t.Fatalf("create membership: %v", err)
+		}
+	}
+
+	svc := NewUserService(db, nil)
+	if err := svc.DeleteMerchantAccount(merchantUser.ID, platformAdmin.ID); err != nil {
+		t.Fatalf("delete merchant account: %v", err)
+	}
+	var memberships int64
+	if err := db.Model(&model.MerchantMember{}).Where("user_id = ?", merchantUser.ID).Count(&memberships).Error; err != nil || memberships != 0 {
+		t.Fatalf("merchant memberships should be removed, count=%d err=%v", memberships, err)
+	}
+	var deleted model.User
+	if err := db.Unscoped().First(&deleted, merchantUser.ID).Error; err != nil || !deleted.DeletedAt.Valid {
+		t.Fatalf("merchant account should be soft deleted, user=%+v err=%v", deleted, err)
+	}
+	if err := svc.DeleteMerchantAccount(platformAdmin.ID, merchantUser.ID); err == nil {
+		t.Fatal("platform administrator should not be deletable from merchant account endpoint")
+	}
+}
diff --git a/backend/internal/service/user.go b/backend/internal/service/user.go
index f961e82..bc7cb23 100644
--- a/backend/internal/service/user.go
+++ b/backend/internal/service/user.go
@@ -316,3 +316,31 @@ func (s *UserService) DeletePlatformAdmin(id, actorUserID uint) error {
 		return tx.Delete(&user).Error
 	})
 }
+
+// DeleteMerchantAccount permanently removes a merchant login account and all
+// of its merchant memberships. Platform administrators must be managed from
+// the dedicated platform administrator view instead.
+func (s *UserService) DeleteMerchantAccount(id, actorUserID uint) error {
+	if id == 0 {
+		return errors.New("用户不存在")
+	}
+	if id == actorUserID {
+		return errors.New("不能删除当前登录账号")
+	}
+	return s.db.Transaction(func(tx *gorm.DB) error {
+		var user model.User
+		if err := tx.First(&user, id).Error; err != nil {
+			if errors.Is(err, gorm.ErrRecordNotFound) {
+				return errors.New("用户不存在")
+			}
+			return err
+		}
+		if user.Role != model.RoleMerchant {
+			return errors.New("平台管理员请在平台管理员列表中管理")
+		}
+		if err := tx.Where("user_id = ?", user.ID).Delete(&model.MerchantMember{}).Error; err != nil {
+			return err
+		}
+		return tx.Delete(&user).Error
+	})
+}
diff --git a/frontend/src/api/index.ts b/frontend/src/api/index.ts
index 2373dde..d073ce0 100644
--- a/frontend/src/api/index.ts
+++ b/frontend/src/api/index.ts
@@ -181,6 +181,8 @@ export const deliveryApi = {
 export const platformApi = {
   merchantAccounts: (params?: Record<string, unknown>) =>
     request.get('/platform/merchant-accounts', { params }).then((r) => r.data.data as PageResult<MerchantMemberGroup>),
+  deleteMerchantAccount: (userId: number) =>
+    request.delete(`/platform/merchant-accounts/${userId}`).then((r) => r.data.data),
   merchants: (params?: Record<string, unknown>) =>
     request.get('/platform/merchants', { params }).then((r) => r.data.data as PageResult<Merchant>),
   createMerchant: (data: {
diff --git a/frontend/src/pages/PlatformUsers.tsx b/frontend/src/pages/PlatformUsers.tsx
index ed442ac..defd1d5 100644
--- a/frontend/src/pages/PlatformUsers.tsx
+++ b/frontend/src/pages/PlatformUsers.tsx
@@ -104,6 +104,16 @@ export default function PlatformUsers() {
     }
   }
 
+  const removeMerchantAccount = async (record: MerchantMember) => {
+    try {
+      await platformApi.deleteMerchantAccount(record.user_id)
+      message.success('商户账号已删除')
+      void loadMerchantAccounts()
+    } catch (e) {
+      message.error(e instanceof Error ? e.message : '删除失败')
+    }
+  }
+
   const columns: ColumnsType<User> = [
     { title: '用户名', dataIndex: 'username', width: 260, render: (value) => <Typography.Text strong>{value}</Typography.Text> },
     { title: '昵称', dataIndex: 'nickname', width: 220, render: (value) => value || '-' },
@@ -128,6 +138,18 @@ export default function PlatformUsers() {
     { title: '昵称', dataIndex: ['user', 'nickname'], width: 220, render: (_, record) => record.user?.nickname || '-' },
     { title: '商户角色', dataIndex: 'role', width: 160, render: (role) => <Tag color="blue">{roleText(role)}</Tag> },
     { title: '成员状态', dataIndex: 'status', width: 130, render: (status) => status === 1 ? <Tag color="green">启用</Tag> : <Tag>停用</Tag> },
+    {
+      title: '操作',
+      width: 120,
+      render: (_, record) => <Popconfirm
+        title={`确认删除商户账号「${record.user?.username || `#${record.user_id}`}」？`}
+        description="该账号会被永久删除，并移除其在所有商户下的成员关系。"
+        onConfirm={() => void removeMerchantAccount(record)}
+        okButtonProps={{ danger: true }}
+      >
+        <Button type="link" danger size="small" icon={<DeleteOutlined />}>删除账号</Button>
+      </Popconfirm>,
+    },
   ]
 
   const merchantColumns: ColumnsType<MerchantMemberGroup> = [