diff --git a/CHANGES.md b/CHANGES.md
index 5edd9e0ee..b7dc0c836 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -23,6 +23,7 @@ Release Notes.
 * Fix argument type name of Array in postgresql-8.x-plugin from java.lang.String[] to [Ljava.lang.String; 
 * Add type name checking in ArgumentTypeNameMatch and ReturnTypeNameMatch
 * Highlight ArgumentTypeNameMatch and ReturnTypeNameMatch type naming rule in docs/en/setup/service-agent/java-agent/Java-Plugin-Development-Guide.md
+* Fix FileWriter scheduled task NPE
 
 #### Documentation
 
diff --git a/apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/logging/core/FileWriter.java b/apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/logging/core/FileWriter.java
index 866bc4f3d..eed675055 100644
--- a/apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/logging/core/FileWriter.java
+++ b/apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/logging/core/FileWriter.java
@@ -73,7 +73,9 @@ public class FileWriter implements IWriter {
                                  writeToFile(log + Constants.LINE_SEPARATOR);
                              }
                              try {
-                                 fileOutputStream.flush();
+                                 if (fileOutputStream != null) {
+                                     fileOutputStream.flush();
+                                 }
                              } catch (IOException e) {
                                  e.printStackTrace();
                              }