diff --git a/fe/fe-core/src/main/java/org/apache/doris/analysis/CreateTableAsSelectStmt.java b/fe/fe-core/src/main/java/org/apache/doris/analysis/CreateTableAsSelectStmt.java
index 2d6ee678db3a52..942c3cce70d6df 100644
--- a/fe/fe-core/src/main/java/org/apache/doris/analysis/CreateTableAsSelectStmt.java
+++ b/fe/fe-core/src/main/java/org/apache/doris/analysis/CreateTableAsSelectStmt.java
@@ -20,7 +20,11 @@
 import org.apache.doris.common.ErrorCode;
 import org.apache.doris.common.ErrorReport;
 import org.apache.doris.common.UserException;
+import org.apache.doris.planner.OriginalPlanner;
+import org.apache.doris.planner.PlanFragment;
+import org.apache.doris.qe.ConnectContext;
 
+import com.google.common.base.Preconditions;
 import lombok.Getter;
 
 import java.util.ArrayList;
@@ -67,6 +71,18 @@ public void analyze(Analyzer analyzer) throws UserException {
         QueryStmt tmpStmt = queryStmt.clone();
         tmpStmt.analyze(dummyRootAnalyzer);
         this.queryStmt = tmpStmt;
+        // to adjust the nullable of the result expression, we have to create plan fragment from the query stmt.
+        OriginalPlanner planner = new OriginalPlanner(dummyRootAnalyzer);
+        planner.createPlanFragments(queryStmt, dummyRootAnalyzer, ConnectContext.get().getSessionVariable().toThrift());
+        PlanFragment root = planner.getFragments().get(0);
+        List<Expr> outputs = root.getOutputExprs();
+        Preconditions.checkArgument(outputs.size() == queryStmt.getResultExprs().size());
+        for (int i = 0; i < outputs.size(); ++i) {
+            if (queryStmt.getResultExprs().get(i).getSrcSlotRef() != null) {
+                queryStmt.getResultExprs().get(i).getSrcSlotRef().getColumn()
+                        .setIsAllowNull(outputs.get(i).isNullable());
+            }
+        }
         ArrayList<Expr> resultExprs = getQueryStmt().getResultExprs();
         if (columnNames != null && columnNames.size() != resultExprs.size()) {
             ErrorReport.reportAnalysisException(ErrorCode.ERR_COL_NUMBER_NOT_MATCH);
diff --git a/fe/fe-core/src/main/java/org/apache/doris/planner/SingleNodePlanner.java b/fe/fe-core/src/main/java/org/apache/doris/planner/SingleNodePlanner.java
index e3fa6978b54808..faeb6183c009be 100644
--- a/fe/fe-core/src/main/java/org/apache/doris/planner/SingleNodePlanner.java
+++ b/fe/fe-core/src/main/java/org/apache/doris/planner/SingleNodePlanner.java
@@ -1055,7 +1055,7 @@ private PlanNode createJoinPlan(Analyzer analyzer, TableRef leftmostRef, List<Pa
                 // reset assigned conjuncts of analyzer in every compare
                 analyzer.setAssignedConjuncts(root.getAssignedConjuncts());
                 PlanNode candidate = createJoinNode(analyzer, root, rootPlanNodeOfCandidate, tblRefOfCandidate);
-                // (ML): 这里还需要吗？应该不会返回null吧
+                // it may not return null, but protect.
                 if (candidate == null) {
                     continue;
                 }
diff --git a/regression-test/suites/ddl_p0/test_ctas.groovy b/regression-test/suites/ddl_p0/test_ctas.groovy
index 35bd4f2726a52e..7c093aa4793593 100644
--- a/regression-test/suites/ddl_p0/test_ctas.groovy
+++ b/regression-test/suites/ddl_p0/test_ctas.groovy
@@ -205,6 +205,39 @@ suite("test_ctas") {
             DROP TABLE IF EXISTS ctas_113815
         """
     }
+    
+    try {
+        sql '''create table a (
+                id int not null,
+                        name varchar(20) not null
+        )
+        distributed by hash(id) buckets 4
+        properties (
+                "replication_num"="1"
+        );
+        '''
+
+        sql '''create table b (
+                id int not null,
+                        age int not null
+        )
+        distributed by hash(id) buckets 4
+        properties (
+                "replication_num"="1"
+        );
+        '''
+
+        sql 'insert into a values(1, \'ww\'), (2, \'zs\');'
+        sql 'insert into b values(1, 22);'
 
+        sql 'create table c properties("replication_num"="1") as select a.id, a.name, b.age from a left join b on a.id = b.id;'
+        
+        String desc = sql 'desc c'
+        assertTrue(desc.contains('Yes'))
+    } finally {
+        sql 'drop table a'
+        sql 'drop table b'
+        sql 'drop table c'
+    }
 }
 
diff --git a/regression-test/suites/delete_p0/test_delete.groovy b/regression-test/suites/delete_p0/test_delete.groovy
index c19884b411fe9e..bcd648c2fdc204 100644
--- a/regression-test/suites/delete_p0/test_delete.groovy
+++ b/regression-test/suites/delete_p0/test_delete.groovy
@@ -233,7 +233,7 @@ suite("test_delete") {
         PROPERTIES (
             "replication_num" = "1",
             "enable_unique_key_merge_on_write" = "true"
-        ); 
+        );
     '''
     
     sql 'insert into test1 values("a", "a"), ("bb", "bb"), ("ccc", "ccc")'