diff --git a/fe/fe-core/src/main/java/org/apache/doris/nereids/rules/expression/rules/SimplifyConditionalFunction.java b/fe/fe-core/src/main/java/org/apache/doris/nereids/rules/expression/rules/SimplifyConditionalFunction.java
index 359cb887fe54b7..c1c6283e32d21c 100644
--- a/fe/fe-core/src/main/java/org/apache/doris/nereids/rules/expression/rules/SimplifyConditionalFunction.java
+++ b/fe/fe-core/src/main/java/org/apache/doris/nereids/rules/expression/rules/SimplifyConditionalFunction.java
@@ -22,6 +22,7 @@
 import org.apache.doris.nereids.trees.expressions.Expression;
 import org.apache.doris.nereids.trees.expressions.functions.scalar.Coalesce;
 import org.apache.doris.nereids.trees.expressions.functions.scalar.NullIf;
+import org.apache.doris.nereids.trees.expressions.functions.scalar.Nullable;
 import org.apache.doris.nereids.trees.expressions.functions.scalar.Nvl;
 import org.apache.doris.nereids.trees.expressions.literal.NullLiteral;
 
@@ -98,7 +99,7 @@ private static Expression rewriteNvl(Nvl nvl) {
      */
     private static Expression rewriteNullIf(NullIf nullIf) {
         if (nullIf.child(0) instanceof NullLiteral || nullIf.child(1) instanceof NullLiteral) {
-            return nullIf.child(0);
+            return new Nullable(nullIf.child(0));
         } else {
             return nullIf;
         }
diff --git a/fe/fe-core/src/test/java/org/apache/doris/nereids/rules/expression/rules/SimplifyConditionalFunctionTest.java b/fe/fe-core/src/test/java/org/apache/doris/nereids/rules/expression/rules/SimplifyConditionalFunctionTest.java
index 33c62f142c22aa..7ba9cf09ff26fd 100644
--- a/fe/fe-core/src/test/java/org/apache/doris/nereids/rules/expression/rules/SimplifyConditionalFunctionTest.java
+++ b/fe/fe-core/src/test/java/org/apache/doris/nereids/rules/expression/rules/SimplifyConditionalFunctionTest.java
@@ -22,6 +22,7 @@
 import org.apache.doris.nereids.trees.expressions.SlotReference;
 import org.apache.doris.nereids.trees.expressions.functions.scalar.Coalesce;
 import org.apache.doris.nereids.trees.expressions.functions.scalar.NullIf;
+import org.apache.doris.nereids.trees.expressions.functions.scalar.Nullable;
 import org.apache.doris.nereids.trees.expressions.functions.scalar.Nvl;
 import org.apache.doris.nereids.trees.expressions.literal.NullLiteral;
 import org.apache.doris.nereids.types.BooleanType;
@@ -99,13 +100,14 @@ public void testNullIf() {
         SlotReference slot = new SlotReference("a", StringType.INSTANCE, true);
         SlotReference nonNullableSlot = new SlotReference("b", StringType.INSTANCE, false);
         // nullif(null, slot) -> null
-        assertRewrite(new NullIf(NullLiteral.INSTANCE, slot), new NullLiteral(VarcharType.SYSTEM_DEFAULT));
+        assertRewrite(new NullIf(NullLiteral.INSTANCE, slot),
+                new Nullable(new NullLiteral(VarcharType.SYSTEM_DEFAULT)));
 
         // nullif(nullable_slot, null) -> slot
-        assertRewrite(new NullIf(slot, NullLiteral.INSTANCE), slot);
+        assertRewrite(new NullIf(slot, NullLiteral.INSTANCE), new Nullable(slot));
 
         // nullif(non-nullable_slot, null) -> non-nullable_slot
-        assertRewrite(new NullIf(nonNullableSlot, NullLiteral.INSTANCE), nonNullableSlot);
+        assertRewrite(new NullIf(nonNullableSlot, NullLiteral.INSTANCE), new Nullable(nonNullableSlot));
     }
 
 }
diff --git a/regression-test/data/nereids_rules_p0/simplify_conditional_function/simplify_conditional_function.out b/regression-test/data/nereids_rules_p0/simplify_conditional_function/simplify_conditional_function.out
index 91f9110804b8b6..d9f4f3b335872c 100644
--- a/regression-test/data/nereids_rules_p0/simplify_conditional_function/simplify_conditional_function.out
+++ b/regression-test/data/nereids_rules_p0/simplify_conditional_function/simplify_conditional_function.out
@@ -131,3 +131,6 @@ abc
 ab
 abc
 
+-- !test_nullable_nullif --
+1	1
+
diff --git a/regression-test/suites/nereids_rules_p0/simplify_conditional_function/simplify_conditional_function.groovy b/regression-test/suites/nereids_rules_p0/simplify_conditional_function/simplify_conditional_function.groovy
index 18443bb152abda..2b99ad0a23a8a5 100644
--- a/regression-test/suites/nereids_rules_p0/simplify_conditional_function/simplify_conditional_function.groovy
+++ b/regression-test/suites/nereids_rules_p0/simplify_conditional_function/simplify_conditional_function.groovy
@@ -49,4 +49,6 @@ suite("simplify_conditional_function") {
     qt_test_outer_ref_coalesce "select c1 from (select coalesce(null,a,c) c1,a,b from test_simplify_conditional_function order by c1,a,b limit 2) t group by c1 order by c1"
     qt_test_outer_ref_nvl "select c1 from (select ifnull(null, c) c1 from test_simplify_conditional_function order by 1 limit 2) t group by c1 order by c1"
     qt_test_outer_ref_nullif "select c1 from (select nullif(a, null) c1,c from test_simplify_conditional_function order by c1,c limit 2 ) t group by c1 order by c1"
+
+    qt_test_nullable_nullif "SELECT COUNT( DISTINCT NULLIF ( 1, NULL ) ), COUNT( DISTINCT 72 )"
 }
\ No newline at end of file