diff --git a/kclvm/ast/src/ast.rs b/kclvm/ast/src/ast.rs
index 6c9c80702..663879f17 100644
--- a/kclvm/ast/src/ast.rs
+++ b/kclvm/ast/src/ast.rs
@@ -1556,7 +1556,7 @@ impl ToString for Type {
                     }
                     for (i, t) in x.type_elements.iter().enumerate() {
                         if i > 0 {
-                            w.push('|');
+                            w.push_str(" | ")
                         }
                         to_str(&t.node, w);
                     }
diff --git a/kclvm/tools/src/format/test_data/format_data/type_alias.golden b/kclvm/tools/src/format/test_data/format_data/type_alias.golden
index 7bc0ef6b1..87616fb37 100644
--- a/kclvm/tools/src/format/test_data/format_data/type_alias.golden
+++ b/kclvm/tools/src/format/test_data/format_data/type_alias.golden
@@ -4,4 +4,4 @@ schema Person:
 
 type PersonOther = Person
 type Int = int
-type UnionType = int|float|str
+type UnionType = int | float | str
diff --git a/kclvm/tools/src/format/test_data/format_data/union_types.golden b/kclvm/tools/src/format/test_data/format_data/union_types.golden
index 86f5bc5d7..b4f853579 100644
--- a/kclvm/tools/src/format/test_data/format_data/union_types.golden
+++ b/kclvm/tools/src/format/test_data/format_data/union_types.golden
@@ -2,4 +2,10 @@ workloadType: "Deployment" | "StatefulSet" = "Deployment"
 ServiceType: "LoadBalance" | "ClusterIP" = "LoadBalance"
 abc: A | B | C = A {}
 
+schema Server:
+    [name: str | int]: str | int
+    workloadType: "Deployment" | "StatefulSet"
+    dict: {str:str | int}
+
+type some_alias = "abc" | "def" | {str | int:}
 # In union types, there should be one and only one whitespace both before and after the union operator |
diff --git a/kclvm/tools/src/format/test_data/format_data/union_types.input b/kclvm/tools/src/format/test_data/format_data/union_types.input
index 0dd6de4f9..03d8b64fd 100644
--- a/kclvm/tools/src/format/test_data/format_data/union_types.input
+++ b/kclvm/tools/src/format/test_data/format_data/union_types.input
@@ -2,4 +2,10 @@ workloadType: "Deployment"|"StatefulSet" = "Deployment"
 ServiceType: "LoadBalance"   |"ClusterIP" = "LoadBalance"
 abc: A|B|C = A{}
 
+schema Server:
+    [name: str|int]: str|int
+    workloadType: "Deployment"|    "StatefulSet"
+    dict: {str: str|int}
+
+type some_alias = "abc"|"def"|{str|int:}
 # In union types, there should be one and only one whitespace both before and after the union operator |
diff --git a/kclvm/tools/src/format/tests.rs b/kclvm/tools/src/format/tests.rs
index 0b483abfe..1acdebfc6 100644
--- a/kclvm/tools/src/format/tests.rs
+++ b/kclvm/tools/src/format/tests.rs
@@ -5,7 +5,7 @@ use walkdir::WalkDir;
 
 const FILE_INPUT_SUFFIX: &str = ".input";
 const FILE_OUTPUT_SUFFIX: &str = ".golden";
-const TEST_CASES: &[&str; 18] = &[
+const TEST_CASES: &[&str; 19] = &[
     "assert",
     "check",
     "blankline",
@@ -24,7 +24,7 @@ const TEST_CASES: &[&str; 18] = &[
     "string",
     "type_alias",
     "unary",
-    // "union_types",
+    "union_types",
     // "different_stmts_line_breaks",
     // "list_dict_schema_expr",
 ];