diff --git a/tools/spec_parser/Dart.g b/tools/spec_parser/Dart.g
index 6605bd9b57f..248d74debdd 100644
--- a/tools/spec_parser/Dart.g
+++ b/tools/spec_parser/Dart.g
@@ -4,6 +4,8 @@
 
 // CHANGES:
 //
+// v0.34 Add support for inline classes.
+//
 // v0.33 This commit does not change the derived language at all. It just
 // changes several rules to use the regexp-like grammar operators to simplify
 // onParts, recordLiteralNoConst, functionTypeTails, and functionType.
@@ -244,6 +246,7 @@ libraryDefinition
 topLevelDefinition
     :    classDeclaration
     |    mixinDeclaration
+    |    inlineClassDeclaration
     |    extensionDeclaration
     |    enumType
     |    typeAlias
@@ -431,6 +434,16 @@ mixinMemberDeclaration
     :    classMemberDeclaration
     ;
 
+inlineClassDeclaration
+    :    FINAL? INLINE CLASS typeWithParameters interfaces?
+         LBRACE (metadata inlineMemberDeclaration)* RBRACE
+    ;
+
+// TODO: We might want to make this more strict.
+inlineMemberDeclaration
+    :    classMemberDeclaration
+    ;
+
 extensionDeclaration
     :    EXTENSION identifier? typeParameters? ON type
          LBRACE (metadata extensionMemberDefinition)* RBRACE
@@ -1613,6 +1626,7 @@ otherIdentifier
     :    ASYNC
     |    BASE
     |    HIDE
+    |    INLINE
     |    OF
     |    ON
     |    SEALED
@@ -1898,6 +1912,10 @@ HIDE
     :    'hide'
     ;
 
+INLINE
+    :    'inline'
+    ;
+
 OF
     :    'of'
     ;