diff --git a/fe/fe-core/src/main/java/org/apache/doris/qe/SessionVariable.java b/fe/fe-core/src/main/java/org/apache/doris/qe/SessionVariable.java
index 1476ce6d05..1cc43c8dc4 100644
--- a/fe/fe-core/src/main/java/org/apache/doris/qe/SessionVariable.java
+++ b/fe/fe-core/src/main/java/org/apache/doris/qe/SessionVariable.java
@@ -1551,7 +1551,7 @@ public class SessionVariable implements Serializable, Writable {
     }
 
     public void setMaxScanQueueMemByte(long scanQueueMemByte) {
-        this.maxScanQueueMemByte = Math.min(scanQueueMemByte, maxExecMemByte / 20);
+        this.maxScanQueueMemByte = Math.min(scanQueueMemByte, maxExecMemByte / 2);
     }
 
     public boolean isSqlQuoteShowCreate() {