diff --git a/apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/jvm/gc/GCProvider.java b/apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/jvm/gc/GCProvider.java
index a72e30e95..2f8aa34b5 100644
--- a/apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/jvm/gc/GCProvider.java
+++ b/apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/jvm/gc/GCProvider.java
@@ -24,7 +24,10 @@ public enum GCProvider {
                 break;
             }
         }
-        this.metricAccessor = new UnknowGC();
+
+        if (metricAccessor == null) {
+            this.metricAccessor = new UnknowGC();
+        }
     }
 
     public List<GC> getGCList() {