diff --git a/dolphinscheduler-api/src/main/java/org/apache/dolphinscheduler/api/service/impl/WorkflowDefinitionServiceImpl.java b/dolphinscheduler-api/src/main/java/org/apache/dolphinscheduler/api/service/impl/WorkflowDefinitionServiceImpl.java
index 43e49a952ba9..87717171bc85 100644
--- a/dolphinscheduler-api/src/main/java/org/apache/dolphinscheduler/api/service/impl/WorkflowDefinitionServiceImpl.java
+++ b/dolphinscheduler-api/src/main/java/org/apache/dolphinscheduler/api/service/impl/WorkflowDefinitionServiceImpl.java
@@ -264,6 +264,9 @@ public Map<String, Object> createWorkflowDefinition(User loginUser,
                     definition.getName(), definition.getCode());
             throw new ServiceException(Status.WORKFLOW_DEFINITION_NAME_EXIST, name);
         }
+
+        validateGlobalParams(globalParams);
+
         List<TaskDefinitionLog> taskDefinitionLogs = generateTaskDefinitionList(taskDefinitionJson);
         List<WorkflowTaskRelationLog> taskRelationList = generateTaskRelationList(taskRelationJson, taskDefinitionLogs);
 
@@ -784,6 +787,9 @@ public Map<String, Object> updateWorkflowDefinition(User loginUser,
             putMsg(result, Status.DESCRIPTION_TOO_LONG_ERROR);
             return result;
         }
+
+        validateGlobalParams(globalParams);
+
         List<TaskDefinitionLog> taskDefinitionLogs = generateTaskDefinitionList(taskDefinitionJson);
         List<WorkflowTaskRelationLog> taskRelationList = generateTaskRelationList(taskRelationJson, taskDefinitionLogs);
 
@@ -820,6 +826,38 @@ public Map<String, Object> updateWorkflowDefinition(User loginUser,
         return result;
     }
 
+    /**
+     * Validates global parameters: non-empty keys, no duplicates
+     */
+    private void validateGlobalParams(String globalParams) {
+        if (StringUtils.isBlank(globalParams)) {
+            return;
+        }
+
+        List<Property> params;
+        try {
+            params = JSONUtils.toList(globalParams, Property.class);
+        } catch (Exception e) {
+            throw new ServiceException("Invalid globalParams");
+        }
+
+        if (params == null || params.isEmpty()) {
+            return;
+        }
+
+        Set<String> keys = new HashSet<>();
+        for (Property p : params) {
+            if (StringUtils.isEmpty(p.getProp())) {
+                throw new ServiceException("Global param key cannot be empty");
+            }
+
+            String key = p.getProp().trim();
+            if (!keys.add(key)) {
+                throw new ServiceException("Duplicate global param key: " + key);
+            }
+        }
+    }
+
     /**
      * Task want to delete whether used in other task, should throw exception when have be used.
      * <p>