diff --git a/yudao-module-bpm/src/main/java/cn/iocoder/yudao/module/bpm/enums/ErrorCodeConstants.java b/yudao-module-bpm/src/main/java/cn/iocoder/yudao/module/bpm/enums/ErrorCodeConstants.java
index ca4bcb3..b815780 100644
--- a/yudao-module-bpm/src/main/java/cn/iocoder/yudao/module/bpm/enums/ErrorCodeConstants.java
+++ b/yudao-module-bpm/src/main/java/cn/iocoder/yudao/module/bpm/enums/ErrorCodeConstants.java
@@ -44,6 +44,7 @@ public interface ErrorCodeConstants {
     ErrorCode PROCESS_INSTANCE_HTTP_CALL_ERROR = new ErrorCode(1_009_004_006, "流程 Http 请求调用失败");
     ErrorCode PROCESS_INSTANCE_APPROVE_USER_SELECT_ASSIGNEES_NOT_CONFIG = new ErrorCode(1_009_004_007, "下一个任务({})的审批人未配置");
     ErrorCode PROCESS_INSTANCE_CANCEL_CHILD_FAIL_NOT_ALLOW = new ErrorCode(1_009_004_008, "子流程取消失败，子流程不允许取消");
+    ErrorCode PROCESS_INSTANCE_START_FORM_FIELD_REQUIRED = new ErrorCode(1_009_004_009, "发起流程失败，表单字段（{}）为必填项，不能为空");
 
     // ========== 流程任务 1-009-005-000 ==========
     ErrorCode TASK_OPERATE_FAIL_ASSIGN_NOT_SELF = new ErrorCode(1_009_005_001, "操作失败，原因：该任务的审批人不是你");
diff --git a/yudao-module-bpm/src/main/java/cn/iocoder/yudao/module/bpm/service/task/BpmProcessInstanceServiceImpl.java b/yudao-module-bpm/src/main/java/cn/iocoder/yudao/module/bpm/service/task/BpmProcessInstanceServiceImpl.java
index a1050ab..d55d3df 100644
--- a/yudao-module-bpm/src/main/java/cn/iocoder/yudao/module/bpm/service/task/BpmProcessInstanceServiceImpl.java
+++ b/yudao-module-bpm/src/main/java/cn/iocoder/yudao/module/bpm/service/task/BpmProcessInstanceServiceImpl.java
@@ -22,6 +22,7 @@ import cn.iocoder.yudao.module.bpm.convert.task.BpmProcessInstanceConvert;
 import cn.iocoder.yudao.module.bpm.dal.dataobject.definition.BpmProcessDefinitionInfoDO;
 import cn.iocoder.yudao.module.bpm.dal.redis.BpmProcessIdRedisDAO;
 import cn.iocoder.yudao.module.bpm.enums.ErrorCodeConstants;
+import cn.iocoder.yudao.module.bpm.enums.definition.BpmModelFormTypeEnum;
 import cn.iocoder.yudao.module.bpm.enums.definition.BpmModelTypeEnum;
 import cn.iocoder.yudao.module.bpm.enums.definition.BpmSimpleModelNodeTypeEnum;
 import cn.iocoder.yudao.module.bpm.enums.task.BpmAttachmentTypeEnum;
@@ -763,11 +764,54 @@ public class BpmProcessInstanceServiceImpl implements BpmProcessInstanceService 
         // 获得流程定义
         ProcessDefinition definition = processDefinitionService
                 .getProcessDefinition(createReqVO.getProcessDefinitionId());
+        // 校验动态表单必填字段（前端校验可被接口直调绕过，后端必须兜底，否则必填缺失也会建成脏实例）
+        validateDynamicFormRequiredFields(definition, createReqVO.getVariables());
         // 发起流程
         return createProcessInstance0(userId, definition, createReqVO.getVariables(), null,
                 createReqVO.getStartUserSelectAssignees());
     }
 
+    /**
+     * 校验动态表单（formType=10 流程表单）的必填字段
+     *
+     * 注意：仅校验接口发起（VO 路径）入口。内部业务链路（DTO 路径，例如 OA 请假）
+     * 由业务代码自行组装变量，不经过本校验，避免误伤。
+     */
+    private void validateDynamicFormRequiredFields(ProcessDefinition definition, Map<String, Object> variables) {
+        BpmProcessDefinitionInfoDO processDefinitionInfo = processDefinitionService
+                .getProcessDefinitionInfo(definition.getId());
+        if (processDefinitionInfo == null
+                || !BpmModelFormTypeEnum.NORMAL.getType().equals(processDefinitionInfo.getFormType())
+                || CollUtil.isEmpty(processDefinitionInfo.getFormFields())) {
+            return;
+        }
+        List<String> fieldStrs = processDefinitionInfo.getFormFields();
+        // formFields 是 JSON 数组，每个元素本身又是 JSON 字符串；两种表单设计器并存：
+        // 字段标识可能是 field 或 key，必填标记可能是数组 ["required"] 或对象 {"required": true}
+        for (String fieldStr : fieldStrs) {
+            Map<String, Object> field = JsonUtils.parseMap(fieldStr);
+            boolean required = false;
+            Object validate = field.get("validate");
+            if (validate instanceof List) {
+                required = ((List<?>) validate).contains("required");
+            } else if (validate instanceof Map) {
+                required = Boolean.TRUE.equals(((Map<?, ?>) validate).get("required"));
+            }
+            if (!required) {
+                continue;
+            }
+            String fieldId = Convert.toStr(field.get("field"), Convert.toStr(field.get("key")));
+            if (StrUtil.isEmpty(fieldId)) {
+                continue;
+            }
+            Object value = variables == null ? null : variables.get(fieldId);
+            if (value == null || (value instanceof String && StrUtil.isBlank((String) value))) {
+                throw exception(PROCESS_INSTANCE_START_FORM_FIELD_REQUIRED,
+                        Convert.toStr(field.get("title"), fieldId));
+            }
+        }
+    }
+
     @Override
     @DataPermission(enable = false) // 关闭数据权限，避免查询不到用户数据。相关案例：https://gitee.com/zhijiantianya/yudao-cloud/issues/ID1UYA
     public String createProcessInstance(Long userId, @Valid BpmProcessInstanceCreateReqDTO createReqDTO) {