diff --git a/CHANGELOG.md b/CHANGELOG.md
index cd53ddff..205c1e80 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,7 @@
 - Added `wrapping.metadataCallParameter` ([#370](https://github.com/HaxeCheckstyle/haxe-formatter/issues/370))
 - Added `emptyLines.macroClassEmptyLines`, fixes [#377](https://github.com/HaxeCheckstyle/haxe-formatter/issues/377) ([#383](https://github.com/HaxeCheckstyle/haxe-formatter/issues/383))
 - Added `emptyLines.lineCommentsBetweenTypes` and `emptyLines.lineCommentsBetweenTypes` to separate line comments from types and functions ([#387](https://github.com/HaxeCheckstyle/haxe-formatter/issues/387))
+- Added `whitespace.addLineCommentSpace` to ensure a space after `//` ([#388](https://github.com/HaxeCheckstyle/haxe-formatter/issues/388))
 - Fixed type parameter constraint with structure type, fixes [#337](https://github.com/HaxeCheckstyle/haxe-formatter/issues/337) ([#349](https://github.com/HaxeCheckstyle/haxe-formatter/issues/349))
 - Fixed wrapping of OpBool chains with null ([#349](https://github.com/HaxeCheckstyle/haxe-formatter/issues/349))
 - Fixed line comments after typedefs, fixes [#331](https://github.com/HaxeCheckstyle/haxe-formatter/issues/331) ([#349](https://github.com/HaxeCheckstyle/haxe-formatter/issues/349))
diff --git a/resources/default-hxformat.json b/resources/default-hxformat.json
index 783241aa..6f107fed 100644
--- a/resources/default-hxformat.json
+++ b/resources/default-hxformat.json
@@ -146,6 +146,7 @@
 		"whileBody": "next"
 	},
 	"whitespace": {
+		"addLineCommentSpace": true,
 		"arrowFunctionsPolicy": "around",
 		"binopPolicy": "around",
 		"bracesConfig": {
diff --git a/resources/formatter-schema.json b/resources/formatter-schema.json
index dcc091ca..09f30904 100644
--- a/resources/formatter-schema.json
+++ b/resources/formatter-schema.json
@@ -1131,6 +1131,11 @@
 					],
 					"propertyOrder": 12
 				},
+				"addLineCommentSpace": {
+					"description": "ensure a space after '//'",
+					"type": "boolean",
+					"propertyOrder": 30
+				},
 				"catchPolicy": {
 					"type": "string",
 					"enum": [
diff --git a/src/formatter/config/WhitespaceConfig.hx b/src/formatter/config/WhitespaceConfig.hx
index 39b3e220..280142cd 100644
--- a/src/formatter/config/WhitespaceConfig.hx
+++ b/src/formatter/config/WhitespaceConfig.hx
@@ -63,6 +63,11 @@ typedef WhitespaceConfig = {
 		only applies spaces, no newlines or wrapping
 	**/
 	@:default(true) @:optional var formatStringInterpolation:Bool;
+
+	/**
+		ensure a space after '//'
+	**/
+	@:default(true) @:optional var addLineCommentSpace:Bool;
 }
 
 typedef ParenWhitespaceConfig = {
diff --git a/src/formatter/marker/MarkTokenText.hx b/src/formatter/marker/MarkTokenText.hx
index 398ce7dc..5a9bdb14 100644
--- a/src/formatter/marker/MarkTokenText.hx
+++ b/src/formatter/marker/MarkTokenText.hx
@@ -255,6 +255,9 @@ class MarkTokenText extends MarkerBase {
 		if (~/^[\/\*\-\s]+/.match(text)) {
 			return "//" + text.rtrim();
 		}
-		return "// " + text.trim();
+		if (config.whitespace.addLineCommentSpace) {
+			return "// " + text.trim();
+		}
+		return "//" + text.trim();
 	}
 }
diff --git a/test/testcases/emptylines/line_comments_between_types.hxtest b/test/testcases/emptylines/line_comments_between_types.hxtest
index 03f9b351..c9331d5e 100644
--- a/test/testcases/emptylines/line_comments_between_types.hxtest
+++ b/test/testcases/emptylines/line_comments_between_types.hxtest
@@ -3,20 +3,20 @@
 
 ---
 
-// class Main {
+//class Main {
 class Main {}
 
-// class Main {
+//class Main {
 typedef Main = String;
-// class Main {
+//class Main {
 
 class Main {}
 
-// class Main {
-// }
+//class Main {
+//}
 typedef Main = String;
-// class Main {
-// }
+//class Main {
+//}
 
 ---
 
diff --git a/test/testcases/emptylines/line_comments_between_types_no_space.hxtest b/test/testcases/emptylines/line_comments_between_types_no_space.hxtest
new file mode 100644
index 00000000..5fbdf3ec
--- /dev/null
+++ b/test/testcases/emptylines/line_comments_between_types_no_space.hxtest
@@ -0,0 +1,44 @@
+{
+	"whitespace" : {
+		"addLineCommentSpace": false
+	}
+}
+
+---
+
+//class Main {
+class Main {}
+
+//class Main {
+typedef Main = String;
+//class Main {
+
+class Main {}
+
+//class Main {
+//}
+typedef Main = String;
+//class Main {
+//}
+
+---
+
+//class Main {
+
+class Main {}
+
+//class Main {
+
+typedef Main = String;
+
+//class Main {
+
+class Main {}
+
+//class Main {
+//}
+
+typedef Main = String;
+
+//class Main {
+//}
diff --git a/test/testcases/whitespace/single_line_comments_no_space.hxtest b/test/testcases/whitespace/single_line_comments_no_space.hxtest
new file mode 100644
index 00000000..7ae6593a
--- /dev/null
+++ b/test/testcases/whitespace/single_line_comments_no_space.hxtest
@@ -0,0 +1,27 @@
+{
+	"whitespace" : {
+		"addLineCommentSpace": false
+	}
+}
+
+---
+
+class Main{
+//*************************
+// Test
+//    Test
+//Test
+///////////////////////////
+static function main(){}
+}
+
+---
+
+class Main {
+	//*************************
+	// Test
+	//    Test
+	//Test
+	///////////////////////////
+	static function main() {}
+}