diff --git a/src/api/oa/erp/timesheetPreAlloc/index.ts b/src/api/oa/erp/timesheetPreAlloc/index.ts
index a6b6fd5..d3a5ac5 100644
--- a/src/api/oa/erp/timesheetPreAlloc/index.ts
+++ b/src/api/oa/erp/timesheetPreAlloc/index.ts
@@ -38,6 +38,17 @@ export const getStaffAllocDetails = (query: { monthCode: string; projectId: stri
   });
 };
 
+/**
+ * 查询当前部门指定月份已填报工时的来源预投项目
+ */
+export const listAvailableSourceProjects = (query: { monthCode: string }): AxiosPromise<any[]> => {
+  return request({
+    url: '/oa/erp/timesheetPreAlloc/listAvailableSourceProjects',
+    method: 'get',
+    params: query
+  });
+};
+
 /**
  * 新增预投工时分配
  * @param data
diff --git a/src/views/oa/erp/timesheetPreAlloc/index.vue b/src/views/oa/erp/timesheetPreAlloc/index.vue
index f9e639a..44eb761 100644
--- a/src/views/oa/erp/timesheetPreAlloc/index.vue
+++ b/src/views/oa/erp/timesheetPreAlloc/index.vue
@@ -25,7 +25,7 @@
             <el-form-item label="预投项目" prop="projectId">
               <el-select v-model="queryParams.projectId" filterable clearable placeholder="请选择预投项目" class="project-select">
                 <el-option
-                  v-for="project in sourceProjectOptions"
+                  v-for="project in querySourceProjectOptions"
                   :key="project.projectId"
                   :label="projectLabel(project)"
                   :value="project.projectId"
@@ -143,7 +143,7 @@
                 clearable
                 :disabled="Boolean(form.allocId)"
                 placeholder="请选择月份"
-                @change="loadStaffAllocDetails"
+                @change="handleMonthChange"
               />
             </el-form-item>
           </el-col>
@@ -248,7 +248,8 @@ import {
   delTimesheetPreAlloc,
   addTimesheetPreAlloc,
   updateTimesheetPreAlloc,
-  getStaffAllocDetails
+  getStaffAllocDetails,
+  listAvailableSourceProjects
 } from '@/api/oa/erp/timesheetPreAlloc';
 import {
   TimesheetPreAllocVO,
@@ -272,6 +273,7 @@ const { alloc_status } = toRefs<any>(proxy?.useDict('alloc_status'));
 
 const timesheetPreAllocList = ref<TimesheetPreAllocVO[]>([]);
 const selectedRows = ref<TimesheetPreAllocVO[]>([]);
+const querySourceProjectOptions = ref<ProjectOption[]>([]);
 const sourceProjectOptions = ref<ProjectOption[]>([]);
 const targetProjectOptions = ref<ProjectOption[]>([]);
 const buttonLoading = ref(false);
@@ -377,9 +379,9 @@ const currentAllocStatus = computed(() => {
 const hasAppliedSelected = computed(() => selectedRows.value.some((row) => row.appliedFlag === '1'));
 
 const loadProjectOptions = async () => {
-  if (sourceProjectOptions.value.length === 0) {
+  if (querySourceProjectOptions.value.length === 0) {
     const sourceRes: any = await getErpProjectInfoList({ projectCategory: '4' });
-    sourceProjectOptions.value = (sourceRes.data || []).map(normalizeProject);
+    querySourceProjectOptions.value = (sourceRes.data || []).map(normalizeProject);
   }
   if (targetProjectOptions.value.length === 0) {
     const [logisticsRes, spareRes]: any[] = await Promise.all([
@@ -393,6 +395,15 @@ const loadProjectOptions = async () => {
   }
 };
 
+const loadSourceProjectOptions = async (monthCode?: string) => {
+  if (!monthCode) {
+    sourceProjectOptions.value = [];
+    return;
+  }
+  const res: any = await listAvailableSourceProjects({ monthCode });
+  sourceProjectOptions.value = (res.data || []).map(normalizeProject);
+};
+
 const normalizeStaffAlloc = (staff: PreAllocStaffAlloc): PreAllocStaffAlloc => ({
   staffUserId: staff.staffUserId,
   staffName: staff.staffName,
@@ -464,6 +475,14 @@ const loadStaffAllocDetails = async () => {
   }
 };
 
+const handleMonthChange = async () => {
+  form.value.projectId = undefined;
+  form.value.projectCode = undefined;
+  form.value.projectName = undefined;
+  form.value.staffAllocList = [];
+  await loadSourceProjectOptions(form.value.monthCode);
+};
+
 const getList = async () => {
   loading.value = true;
   const params = {
@@ -506,6 +525,7 @@ const handleSelectionChange = (selection: TimesheetPreAllocVO[]) => {
 const handleAdd = async () => {
   reset();
   await loadProjectOptions();
+  await loadSourceProjectOptions(form.value.monthCode);
   dialog.visible = true;
   dialog.title = '预投工时分配';
 };