diff --git a/crates/oxc_parser/src/diagnostics.rs b/crates/oxc_parser/src/diagnostics.rs
index cf938ae9a..469c11d6c 100644
--- a/crates/oxc_parser/src/diagnostics.rs
+++ b/crates/oxc_parser/src/diagnostics.rs
@@ -23,10 +23,6 @@ pub struct ExpectToken(pub &'static str, pub &'static str, #[label("`{0}` expect
 #[error("Invalid escape sequence")]
 pub struct InvalidEscapeSequence(#[label] pub Span);
 
-#[derive(Debug, Error, Diagnostic)]
-#[error("\\8 and \\9 are not allowed in strict mode")]
-pub struct NonOctalDecimalEscapeSequence(#[label] pub Span);
-
 #[derive(Debug, Error, Diagnostic)]
 #[error("Invalid Unicode escape sequence")]
 pub struct UnicodeEscapeSequence(#[label] pub Span);
@@ -77,11 +73,6 @@ pub struct EscapedKeyword(#[label] pub Span);
 #[diagnostic(help("Try insert a semicolon here"))]
 pub struct AutoSemicolonInsertion(#[label] pub Span);
 
-#[derive(Debug, Error, Diagnostic)]
-#[error("'0'-prefixed octal literals and octal escape sequences are deprecated")]
-#[diagnostic(help("for octal literals use the '0o' prefix instead"))]
-pub struct LegacyOctal(#[label] pub Span);
-
 #[derive(Debug, Error, Diagnostic)]
 #[error("Line terminator not permitted before arrow")]
 #[diagnostic()]
@@ -232,11 +223,6 @@ pub struct TemplateLiteral(#[label] pub Span);
 #[diagnostic()]
 pub struct EmptyParenthesizedExpression(#[label] pub Span);
 
-#[derive(Debug, Error, Diagnostic)]
-#[error("'{0}' keyword is unexpected here")]
-#[diagnostic()]
-pub struct UnexpectedKeyword(pub &'static str, #[label] pub Span);
-
 #[derive(Debug, Error, Diagnostic)]
 #[error("Illegal newline after {0}")]
 #[diagnostic()]
@@ -295,10 +281,3 @@ pub struct ReturnStatementOnlyInFunctionBody(#[label] pub Span);
 #[error("TS18007: JSX expressions may not use the comma operator.")]
 #[diagnostic(help("Did you mean to write an array?"))]
 pub struct JSXExpressionsMayNotUseTheCommaOperator(#[label] pub Span);
-
-#[derive(Debug, Error, Diagnostic)]
-#[error("Leading decorators must be attached to a class declaration")]
-#[diagnostic()]
-pub struct BadLeadingDecorator(
-    #[label("Leading decorators must be attached to a class declaration")] pub Span,
-);
diff --git a/crates/oxc_parser/src/js/statement.rs b/crates/oxc_parser/src/js/statement.rs
index e34bc8329..9aea2d829 100644
--- a/crates/oxc_parser/src/js/statement.rs
+++ b/crates/oxc_parser/src/js/statement.rs
@@ -270,7 +270,7 @@ impl<'a> Parser<'a> {
                 self.error(diagnostics::ForLoopAsyncOf(self.end_span(expr_span)));
             }
             if is_let_of {
-                self.error(diagnostics::UnexpectedKeyword("let", self.end_span(expr_span)));
+                self.error(diagnostics::UnexpectedToken(self.end_span(expr_span)));
             }
             return self.parse_for_in_or_of_loop(span, r#await, for_stmt_left);
         }