diff --git a/grammars/csharp.tmLanguage b/grammars/csharp.tmLanguage
index 3906d58..aeaeb81 100644
--- a/grammars/csharp.tmLanguage
+++ b/grammars/csharp.tmLanguage
@@ -668,7 +668,7 @@
       <key>attribute-section</key>
       <dict>
         <key>begin</key>
-        <string>(\[)(assembly|module|field|event|method|param|property|return|type)?(\:)?</string>
+        <string>(\[)(assembly|module|field|event|method|param|property|return|typevar|type)?(\:)?</string>
         <key>beginCaptures</key>
         <dict>
           <key>1</key>
diff --git a/grammars/csharp.tmLanguage.cson b/grammars/csharp.tmLanguage.cson
index 0fb74a7..7fed1a0 100644
--- a/grammars/csharp.tmLanguage.cson
+++ b/grammars/csharp.tmLanguage.cson
@@ -447,7 +447,7 @@ repository:
       }
     ]
   "attribute-section":
-    begin: "(\\[)(assembly|module|field|event|method|param|property|return|type)?(\\:)?"
+    begin: "(\\[)(assembly|module|field|event|method|param|property|return|typevar|type)?(\\:)?"
     beginCaptures:
       "1":
         name: "punctuation.squarebracket.open.cs"
diff --git a/src/csharp.tmLanguage.yml b/src/csharp.tmLanguage.yml
index 4576f37..a012a52 100644
--- a/src/csharp.tmLanguage.yml
+++ b/src/csharp.tmLanguage.yml
@@ -189,7 +189,7 @@ repository:
       - include: '#operator-assignment'
 
   attribute-section:
-    begin: (\[)(assembly|module|field|event|method|param|property|return|type)?(\:)?
+    begin: (\[)(assembly|module|field|event|method|param|property|return|typevar|type)?(\:)?
     beginCaptures:
       '1': { name: punctuation.squarebracket.open.cs }
       '2': { name: keyword.other.attribute-specifier.cs }
diff --git a/test/attribute.tests.ts b/test/attribute.tests.ts
index e1f9def..cc367fb 100644
--- a/test/attribute.tests.ts
+++ b/test/attribute.tests.ts
@@ -253,5 +253,36 @@ describe("Attributes", () => {
                     Token.Punctuation.TypeParameter.End,
                     Token.Punctuation.CloseBracket]);
         });
+
+        it("typevar attribute specifier", async () => {
+
+            const input = `[typevar: MyAttribute]`;
+            const tokens = await tokenize(input);
+
+            tokens.should.deep.equal([
+                Token.Punctuation.OpenBracket,
+                Token.Keyword.AttributeSpecifier("typevar"),
+                Token.Punctuation.Colon,
+                Token.Type("MyAttribute"),
+                Token.Punctuation.CloseBracket]);
+        });
+
+        it("typevar attribute specifier on generic type parameter", async () => {
+
+            const input = `class Foo<[typevar: MyAttribute] T>`;
+            const tokens = await tokenize(input);
+
+            tokens.should.deep.equal([
+                Token.Keyword.Definition.Class,
+                Token.Identifier.ClassName("Foo"),
+                Token.Punctuation.TypeParameter.Begin,
+                Token.Punctuation.OpenBracket,
+                Token.Keyword.AttributeSpecifier("typevar"),
+                Token.Punctuation.Colon,
+                Token.Type("MyAttribute"),
+                Token.Punctuation.CloseBracket,
+                Token.Identifier.TypeParameterName("T"),
+                Token.Punctuation.TypeParameter.End]);
+        });
     });
 });