diff --git a/dolphinscheduler-common/src/main/java/org/apache/dolphinscheduler/common/utils/PropertyUtils.java b/dolphinscheduler-common/src/main/java/org/apache/dolphinscheduler/common/utils/PropertyUtils.java
index 87278cdfae..972f17a8d5 100644
--- a/dolphinscheduler-common/src/main/java/org/apache/dolphinscheduler/common/utils/PropertyUtils.java
+++ b/dolphinscheduler-common/src/main/java/org/apache/dolphinscheduler/common/utils/PropertyUtils.java
@@ -88,6 +88,9 @@ public class PropertyUtils {
      * @return property value
      */
     public static String getString(String key) {
+        if (key == null) {
+            return null;
+        }
         return properties.getProperty(key.trim());
     }