diff --git a/fe/fe-core/src/main/java/org/apache/doris/nereids/trees/expressions/functions/agg/Sum.java b/fe/fe-core/src/main/java/org/apache/doris/nereids/trees/expressions/functions/agg/Sum.java
index 87992039361095..f0dbd839583857 100644
--- a/fe/fe-core/src/main/java/org/apache/doris/nereids/trees/expressions/functions/agg/Sum.java
+++ b/fe/fe-core/src/main/java/org/apache/doris/nereids/trees/expressions/functions/agg/Sum.java
@@ -114,7 +114,7 @@ public List<FunctionSignature> getSignatures() {
     @Override
     public FunctionSignature searchSignature(List<FunctionSignature> signatures) {
         if (getArgument(0).getDataType() instanceof FloatType) {
-            return FunctionSignature.ret(DoubleType.INSTANCE).args(DoubleType.INSTANCE);
+            return FunctionSignature.ret(DoubleType.INSTANCE).args(FloatType.INSTANCE);
         }
         return ExplicitlyCastableSignature.super.searchSignature(signatures);
     }
diff --git a/regression-test/suites/nereids_function_p0/agg_function/agg.groovy b/regression-test/suites/nereids_function_p0/agg_function/agg.groovy
index 1a12fd0383de5f..81c84ad32d8f7e 100644
--- a/regression-test/suites/nereids_function_p0/agg_function/agg.groovy
+++ b/regression-test/suites/nereids_function_p0/agg_function/agg.groovy
@@ -2188,6 +2188,12 @@ suite("nereids_agg_fn") {
 	qt_sql_sum_BigInt_agg_phase_4_notnull '''
 		select /*+SET_VAR(disable_nereids_rules='THREE_PHASE_AGGREGATE_WITH_DISTINCT, TWO_PHASE_AGGREGATE_WITH_DISTINCT')*/ count(distinct id), sum(kbint) from fn_test'''
 
+	//not cast float to double
+    explain {
+        sql("select sum(kfloat) from fn_test;")
+        contains "partial_sum(kfloat"
+    }
+
 	qt_sql_sum_Double_gb '''
 		select sum(kdbl) from fn_test group by kbool order by kbool'''
 	qt_sql_sum_Double '''