diff --git a/src/frontend/src/handler/create_sql_function.rs b/src/frontend/src/handler/create_sql_function.rs
index 166e940b60810..4f3f7cfa0117b 100644
--- a/src/frontend/src/handler/create_sql_function.rs
+++ b/src/frontend/src/handler/create_sql_function.rs
@@ -29,7 +29,7 @@ use thiserror_ext::AsReport;
 use super::*;
 use crate::binder::UdfContext;
 use crate::catalog::CatalogError;
-use crate::expr::{ExprImpl, Literal};
+use crate::expr::{Expr, ExprImpl, Literal};
 use crate::{bind_data_type, Binder};
 
 /// Create a mock `udf_context`, which is used for semantic check
@@ -176,12 +176,27 @@ pub async fn handle_create_sql_function(
             .update_context(create_mock_udf_context(arg_types.clone()));
 
         if let Ok(expr) = UdfContext::extract_udf_expression(ast) {
-            if let Err(e) = binder.bind_expr(expr) {
+            let bind_result = binder.bind_expr(expr);
+
+            if let Err(e) = &bind_result {
                 return Err(ErrorCode::InvalidInputSyntax(format!(
                     "failed to conduct semantic check, please see if you are calling non-existence functions: {}",
                     e.as_report()
                 ))
                 .into());
+            } else {
+                // We can safely unwrap here
+                let e = bind_result.unwrap();
+
+                // Check if the return type mismatches
+                if e.return_type() != return_type {
+                    return Err(ErrorCode::InvalidInputSyntax(format!(
+                        "return type mismatch detected\nexpected: {}\nactual: {}\nplease adjust your function definition accordingly",
+                        return_type,
+                        e.return_type()
+                    ))
+                    .into());
+                }
             }
         } else {
             return Err(ErrorCode::InvalidInputSyntax(