diff --git a/src/compiler/diagnosticInformationMap.generated.ts b/src/compiler/diagnosticInformationMap.generated.ts
index 55dd45df789..cc789bcca11 100644
--- a/src/compiler/diagnosticInformationMap.generated.ts
+++ b/src/compiler/diagnosticInformationMap.generated.ts
@@ -105,6 +105,7 @@ module ts {
         An_object_literal_cannot_have_multiple_get_Slashset_accessors_with_the_same_name: { code: 1118, category: DiagnosticCategory.Error, key: "An object literal cannot have multiple get/set accessors with the same name." },
         An_object_literal_cannot_have_property_and_accessor_with_the_same_name: { code: 1119, category: DiagnosticCategory.Error, key: "An object literal cannot have property and accessor with the same name." },
         An_export_assignment_cannot_have_modifiers: { code: 1120, category: DiagnosticCategory.Error, key: "An export assignment cannot have modifiers." },
+        Octal_literals_are_not_allowed_in_strict_mode: { code: 1121, category: DiagnosticCategory.Error, key: "Octal literals are not allowed in strict mode." },
         Duplicate_identifier_0: { code: 2000, category: DiagnosticCategory.Error, key: "Duplicate identifier '{0}'." },
         Extends_clause_of_exported_class_0_has_or_is_using_private_name_1: { code: 2018, category: DiagnosticCategory.Error, key: "Extends clause of exported class '{0}' has or is using private name '{1}'." },
         Implements_clause_of_exported_class_0_has_or_is_using_private_name_1: { code: 2019, category: DiagnosticCategory.Error, key: "Implements clause of exported class '{0}' has or is using private name '{1}'." },
diff --git a/src/compiler/diagnosticMessages.json b/src/compiler/diagnosticMessages.json
index 30e3489374f..d60fd2e5c4f 100644
--- a/src/compiler/diagnosticMessages.json
+++ b/src/compiler/diagnosticMessages.json
@@ -412,6 +412,10 @@
         "category": "Error",
         "code": 1120
     },
+    "Octal literals are not allowed in strict mode.": {
+        "category": "Error",
+        "code": 1121
+    },
     "Duplicate identifier '{0}'.": {
         "category": "Error",
         "code": 2000
diff --git a/src/compiler/parser.ts b/src/compiler/parser.ts
index 929e676c305..57e23531398 100644
--- a/src/compiler/parser.ts
+++ b/src/compiler/parser.ts
@@ -1056,7 +1056,23 @@ module ts {
             var node = <LiteralExpression>createNode(token);
             node.text = scanner.getTokenValue();
             nextToken();
-            return finishNode(node);
+            finishNode(node);
+            
+            // Octal literals are not allowed in strict mode or ES5
+            if (node.kind === SyntaxKind.NumericLiteral && (isInStrictMode || languageVersion >= ScriptTarget.ES5)) {
+                var numberLiteralSource = getSourceTextOfNodeFromSourceText(sourceText, node);
+                // This regex checks if the number is written in octal
+                if (/0[0-7]+/.test(numberLiteralSource)) {
+                    if (isInStrictMode) {
+                        grammarErrorOnNode(node, Diagnostics.Octal_literals_are_not_allowed_in_strict_mode);
+                    }
+                    else {
+                        grammarErrorOnNode(node, Diagnostics.Octal_literals_are_not_available_when_targeting_ECMAScript_5_and_higher);
+                    }
+                }
+            }
+
+            return node;
         }
 
         function parseStringLiteral(): LiteralExpression {
diff --git a/tests/baselines/reference/literals.errors.txt b/tests/baselines/reference/literals.errors.txt
index edfdad8c279..3361dfd5c67 100644
--- a/tests/baselines/reference/literals.errors.txt
+++ b/tests/baselines/reference/literals.errors.txt
@@ -1,4 +1,4 @@
-==== tests/cases/conformance/expressions/literals/literals.ts (4 errors) ====
+==== tests/cases/conformance/expressions/literals/literals.ts (6 errors) ====
     
     //typeof null is Null
     //typeof true is Boolean
@@ -27,11 +27,15 @@
     var n = 1.0;
     var n = 1e4;
     var n = 001; // Error in ES5
+            ~~~
+!!! Octal literals are not available when targeting ECMAScript 5 and higher.
     var n = 0x1;
     var n = -1;
     var n = -1.0;
     var n = -1e-4;
     var n = -003; // Error in ES5
+             ~~~
+!!! Octal literals are not available when targeting ECMAScript 5 and higher.
     var n = -0x1;
     
     var s: string;
diff --git a/tests/baselines/reference/literals.js b/tests/baselines/reference/literals.js
deleted file mode 100644
index da11b6cef49..00000000000
--- a/tests/baselines/reference/literals.js
+++ /dev/null
@@ -1,68 +0,0 @@
-//// [literals.ts]
-
-//typeof null is Null
-//typeof true is Boolean
-//typeof false is Boolean
-//typeof numeric literal is Number
-//typeof string literal is String
-//typeof regex literal is Regex
-
-var nu = null / null;
-var u = undefined / undefined;
-
-var b: boolean;
-var b = true;
-var b = false;
-
-var n: number;
-var n = 1;
-var n = 1.0;
-var n = 1e4;
-var n = 001; // Error in ES5
-var n = 0x1;
-var n = -1;
-var n = -1.0;
-var n = -1e-4;
-var n = -003; // Error in ES5
-var n = -0x1;
-
-var s: string;
-var s = '';
-var s = "";
-var s = 'foo\
-    bar';
-var s = "foo\
-    bar";
-
-var r: RegExp;
-var r = /what/;
-var r = /\\\\/;
-
-
-//// [literals.js]
-var nu = null / null;
-var u = undefined / undefined;
-var b;
-var b = true;
-var b = false;
-var n;
-var n = 1;
-var n = 1.0;
-var n = 1e4;
-var n = 001;
-var n = 0x1;
-var n = -1;
-var n = -1.0;
-var n = -1e-4;
-var n = -003;
-var n = -0x1;
-var s;
-var s = '';
-var s = "";
-var s = 'foo\
-    bar';
-var s = "foo\
-    bar";
-var r;
-var r = /what/;
-var r = /\\\\/;
diff --git a/tests/baselines/reference/objectLiteralErrors.errors.txt b/tests/baselines/reference/objectLiteralErrors.errors.txt
index 8e1b64f1758..6a36b93edbb 100644
--- a/tests/baselines/reference/objectLiteralErrors.errors.txt
+++ b/tests/baselines/reference/objectLiteralErrors.errors.txt
@@ -1,4 +1,4 @@
-==== tests/cases/conformance/expressions/objectLiterals/objectLiteralErrors.ts (59 errors) ====
+==== tests/cases/conformance/expressions/objectLiterals/objectLiteralErrors.ts (61 errors) ====
     
     // Multiple properties with the same name
     var e1 = { a: 0, a: 0 };
@@ -45,6 +45,8 @@
 !!! Duplicate identifier '0x0'.
     var e14 = { 0: 0, 000: 0 };
                       ~~~
+!!! Octal literals are not available when targeting ECMAScript 5 and higher.
+                      ~~~
 !!! Duplicate identifier '000'.
     var e15 = { "100": 0, 1e2: 0 };
                           ~~~
@@ -129,6 +131,8 @@
 !!! Duplicate identifier '0x0'.
     var f14 = { 0: 0, get 000() { return 0; } };
                           ~~~
+!!! Octal literals are not available when targeting ECMAScript 5 and higher.
+                          ~~~
 !!! An object literal cannot have property and accessor with the same name.
                           ~~~
 !!! Duplicate identifier '000'.
diff --git a/tests/baselines/reference/scannerNumericLiteral2.errors.txt b/tests/baselines/reference/scannerNumericLiteral2.errors.txt
new file mode 100644
index 00000000000..c9160bffdf2
--- /dev/null
+++ b/tests/baselines/reference/scannerNumericLiteral2.errors.txt
@@ -0,0 +1,4 @@
+==== tests/cases/conformance/scanner/ecmascript5/scannerNumericLiteral2.ts (1 errors) ====
+    01
+    ~~
+!!! Octal literals are not available when targeting ECMAScript 5 and higher.
\ No newline at end of file
diff --git a/tests/baselines/reference/scannerNumericLiteral2.js b/tests/baselines/reference/scannerNumericLiteral2.js
deleted file mode 100644
index 382f1e6e4df..00000000000
--- a/tests/baselines/reference/scannerNumericLiteral2.js
+++ /dev/null
@@ -1,5 +0,0 @@
-//// [scannerNumericLiteral2.ts]
-01
-
-//// [scannerNumericLiteral2.js]
-01;
diff --git a/tests/baselines/reference/scannerNumericLiteral3.errors.txt b/tests/baselines/reference/scannerNumericLiteral3.errors.txt
index 6f82581759b..ac751dd9089 100644
--- a/tests/baselines/reference/scannerNumericLiteral3.errors.txt
+++ b/tests/baselines/reference/scannerNumericLiteral3.errors.txt
@@ -1,4 +1,6 @@
-==== tests/cases/conformance/scanner/ecmascript5/scannerNumericLiteral3.ts (1 errors) ====
+==== tests/cases/conformance/scanner/ecmascript5/scannerNumericLiteral3.ts (2 errors) ====
     01.0
+    ~~
+!!! Octal literals are not available when targeting ECMAScript 5 and higher.
       ~~
 !!! ';' expected.
\ No newline at end of file