diff --git a/crates/oxc_parser/src/js/class.rs b/crates/oxc_parser/src/js/class.rs
index 1e5f432ab9653..f4346df57f628 100644
--- a/crates/oxc_parser/src/js/class.rs
+++ b/crates/oxc_parser/src/js/class.rs
@@ -231,7 +231,7 @@ impl<'a> ParserImpl<'a> {
         if self.is_at_ts_index_signature_member() {
             return self
                 .parse_index_signature_declaration(span, &modifiers)
-                .map(ClassElement::TSIndexSignature)
+                .map(|sig| self.ast.class_element_from_ts_index_signature(sig))
                 .map(Some);
         }
 
diff --git a/crates/oxc_parser/src/ts/statement.rs b/crates/oxc_parser/src/ts/statement.rs
index 4123f05b859ef..9a81d0debfbc3 100644
--- a/crates/oxc_parser/src/ts/statement.rs
+++ b/crates/oxc_parser/src/ts/statement.rs
@@ -206,7 +206,12 @@ impl<'a> ParserImpl<'a> {
 
     pub(crate) fn parse_ts_type_signature(&mut self) -> Result<Option<TSSignature<'a>>> {
         if self.is_at_ts_index_signature_member() {
-            return self.parse_ts_index_signature_member().map(Some);
+            let span = self.start_span();
+            let modifiers = self.parse_modifiers(false, false, false);
+            return self
+                .parse_index_signature_declaration(span, &modifiers)
+                .map(|sig| self.ast.ts_signature_from_ts_index_signature(sig))
+                .map(Some);
         }
 
         match self.cur_kind() {
diff --git a/crates/oxc_parser/src/ts/types.rs b/crates/oxc_parser/src/ts/types.rs
index 732c1b36b3895..a985bd99f7499 100644
--- a/crates/oxc_parser/src/ts/types.rs
+++ b/crates/oxc_parser/src/ts/types.rs
@@ -1271,7 +1271,7 @@ impl<'a> ParserImpl<'a> {
         &mut self,
         span: Span,
         modifiers: &Modifiers<'a>,
-    ) -> Result<Box<'a, TSIndexSignature<'a>>> {
+    ) -> Result<TSIndexSignature<'a>> {
         self.verify_modifiers(
             modifiers,
             ModifierFlags::READONLY | ModifierFlags::STATIC,
@@ -1284,7 +1284,7 @@ impl<'a> ParserImpl<'a> {
             return Err(self.unexpected());
         };
         self.parse_type_member_semicolon();
-        Ok(self.ast.alloc_ts_index_signature(
+        Ok(self.ast.ts_index_signature(
             self.end_span(span),
             parameters,
             type_annotation,
@@ -1303,35 +1303,6 @@ impl<'a> ParserImpl<'a> {
         self.bump(Kind::Semicolon);
     }
 
-    pub(crate) fn parse_ts_index_signature_member(&mut self) -> Result<TSSignature<'a>> {
-        let span = self.start_span();
-
-        let modifiers = self.parse_class_element_modifiers(false);
-        self.verify_modifiers(
-            &modifiers,
-            ModifierFlags::READONLY | ModifierFlags::STATIC,
-            diagnostics::cannot_appear_on_an_index_signature,
-        );
-
-        self.bump(Kind::LBrack);
-        let index_name = self.parse_ts_index_signature_name()?;
-        let mut parameters = self.ast.vec();
-        parameters.push(index_name);
-        self.expect(Kind::RBrack)?;
-
-        let type_annotation = self.parse_ts_type_annotation()?;
-        let Some(type_annotation) = type_annotation else { return Err(self.unexpected()) };
-        self.bump(Kind::Comma);
-        self.bump(Kind::Semicolon);
-        Ok(self.ast.ts_signature_index_signature(
-            self.end_span(span),
-            parameters,
-            type_annotation,
-            modifiers.contains(ModifierKind::Readonly),
-            modifiers.contains(ModifierKind::Static),
-        ))
-    }
-
     fn parse_ts_index_signature_name(&mut self) -> Result<TSIndexSignatureName<'a>> {
         let span = self.start_span();
         let name = self.parse_identifier_name()?.name;