diff --git a/src/ast/dml/parts/order_by.rs b/src/ast/dml/parts/order_by.rs
index 4214911..c71c692 100644
--- a/src/ast/dml/parts/order_by.rs
+++ b/src/ast/dml/parts/order_by.rs
@@ -7,7 +7,7 @@ pub struct OrderByClause {
     pub order_by_items: Vec<OrderByItem>,
 }
 
-#[derive(Deserialize, Serialize, Clone, Debug, PartialEq)]
+#[derive(Deserialize, Serialize, Clone, Debug, PartialEq, Default)]
 pub struct OrderByItem {
     pub item: SQLExpression,
     pub order_type: OrderByType,
@@ -20,8 +20,20 @@ pub enum OrderByType {
     Desc,
 }
 
+impl Default for OrderByType {
+    fn default() -> Self {
+        OrderByType::Asc
+    }
+}
+
 #[derive(Deserialize, Serialize, Clone, Debug, PartialEq, Eq)]
 pub enum OrderByNulls {
     First,
     Last,
 }
+
+impl Default for OrderByNulls {
+    fn default() -> Self {
+        OrderByNulls::Last
+    }
+}
diff --git a/src/ast/types/expression.rs b/src/ast/types/expression.rs
index a8e53e1..6c2930a 100644
--- a/src/ast/types/expression.rs
+++ b/src/ast/types/expression.rs
@@ -37,6 +37,12 @@ pub enum SQLExpression {
     Null,
 }
 
+impl Default for SQLExpression {
+    fn default() -> Self {
+        Self::Null
+    }
+}
+
 impl SQLExpression {
     pub fn is_unary(&self) -> bool {
         #[allow(clippy::match_like_matches_macro)]
diff --git a/src/parser/test/select.rs b/src/parser/test/select.rs
index 0cf4e54..ff22cba 100644
--- a/src/parser/test/select.rs
+++ b/src/parser/test/select.rs
@@ -1859,3 +1859,114 @@ fn test_parse_select_item() {
         }
     }
 }
+
+#[test]
+fn test_parse_order_by_item() {
+    struct TestCase {
+        name: String,
+        input: Vec<Token>,
+        expected: OrderByItem,
+        want_error: bool,
+    }
+
+    let test_cases = vec![
+        TestCase {
+            name: "p.id ASC".into(),
+            input: vec![
+                Token::Identifier("p".into()),
+                Token::Period,
+                Token::Identifier("id".into()),
+                Token::Asc,
+            ],
+            expected: OrderByItem {
+                item: SelectColumn::new(Some("p".into()), "id".into()).into(),
+                order_type: OrderByType::Asc,
+                nulls: OrderByNulls::First,
+            },
+            want_error: false,
+        },
+        TestCase {
+            name: "p.id DESC".into(),
+            input: vec![
+                Token::Identifier("p".into()),
+                Token::Period,
+                Token::Identifier("id".into()),
+                Token::Desc,
+            ],
+            expected: OrderByItem {
+                item: SelectColumn::new(Some("p".into()), "id".into()).into(),
+                order_type: OrderByType::Desc,
+                nulls: OrderByNulls::First,
+            },
+            want_error: false,
+        },
+        TestCase {
+            name: "p.id NULLS FIRST".into(),
+            input: vec![
+                Token::Identifier("p".into()),
+                Token::Period,
+                Token::Identifier("id".into()),
+                Token::Nulls,
+                Token::First,
+            ],
+            expected: OrderByItem {
+                item: SelectColumn::new(Some("p".into()), "id".into()).into(),
+                order_type: OrderByType::Asc,
+                nulls: OrderByNulls::First,
+            },
+            want_error: false,
+        },
+        TestCase {
+            name: "p.id NULLS LAST".into(),
+            input: vec![
+                Token::Identifier("p".into()),
+                Token::Period,
+                Token::Identifier("id".into()),
+                Token::Nulls,
+                Token::Last,
+            ],
+            expected: OrderByItem {
+                item: SelectColumn::new(Some("p".into()), "id".into()).into(),
+                order_type: OrderByType::Asc,
+                nulls: OrderByNulls::Last,
+            },
+            want_error: false,
+        },
+        TestCase {
+            name: "실패: 빈 토큰".into(),
+            input: vec![],
+            expected: Default::default(),
+            want_error: true,
+        },
+        TestCase {
+            name: "실패: p.id NULLS".into(),
+            input: vec![
+                Token::Identifier("p".into()),
+                Token::Period,
+                Token::Identifier("id".into()),
+                Token::Nulls,
+            ],
+            expected: Default::default(),
+            want_error: true,
+        },
+    ];
+
+    for t in test_cases {
+        let mut parser = Parser::new(t.input);
+
+        let got = parser.parse_order_by_item(Default::default());
+
+        assert_eq!(
+            got.is_err(),
+            t.want_error,
+            "{}: want_error: {}, error: {:?}",
+            t.name,
+            t.want_error,
+            got.err()
+        );
+
+        if let Ok(statements) = got {
+            assert_eq!(statements, t.expected, "TC: {}", t.name);
+        }
+    }
+}