diff --git a/README.md b/README.md
index 3abee55..134dcfc 100644
--- a/README.md
+++ b/README.md
@@ -10,6 +10,10 @@ Extension for [CSS Modules](https://github.com/css-modules/css-modules), which s
 - Autocomplete
 - Go to definition
 
+## Additional Features
+
+- **Experimental:** SASS (.sass) file support for class name completion
+
 ## Demo
 
 ![](https://i.giphy.com/l0EwY2Mk4IBgIholi.gif)
diff --git a/src/test/constant.ts b/src/test/constant.ts
index cff060a..b0220f9 100644
--- a/src/test/constant.ts
+++ b/src/test/constant.ts
@@ -10,4 +10,9 @@ export const SAMPLE_TS_FILE = path.join(FIXTURES_PATH, "sample.ts");
 export const SAMPLE_ASTRO_FILE = path.join(FIXTURES_PATH, "sample.astro");
 export const STYLUS_JSX_FILE = path.join(FIXTURES_PATH, "stylus.jsx");
 export const JUMP_PRECISE_DEF_FILE = path.join(FIXTURES_PATH, "jumpDef.jsx");
-export const SPREAD_SYNTAX_FILE = path.join(FIXTURES_PATH, "spread-syntax", "index.js");
+export const SPREAD_SYNTAX_FILE = path.join(
+  FIXTURES_PATH,
+  "spread-syntax",
+  "index.js"
+);
+export const SASS_JSX_FILE = path.join(FIXTURES_PATH, "sass.jsx");
diff --git a/src/test/fixtures/sample.sass b/src/test/fixtures/sample.sass
new file mode 100644
index 0000000..b6fd3d0
--- /dev/null
+++ b/src/test/fixtures/sample.sass
@@ -0,0 +1,20 @@
+.foo
+  color: red
+
+.bar, .baz
+  background: blue
+
+.parent
+  &.active
+    color: green
+  & .activeSpace
+    color: blue
+  > .child
+    color: yellow
+  + .sibling
+    color: orange
+  ~ .other
+    color: purple
+
+  .complex, &.compound, >.direct, +.adjacent, ~.general
+    border: 1px solid black 
\ No newline at end of file
diff --git a/src/test/fixtures/sass.jsx b/src/test/fixtures/sass.jsx
new file mode 100644
index 0000000..357be4f
--- /dev/null
+++ b/src/test/fixtures/sass.jsx
@@ -0,0 +1,21 @@
+import styles from "./sample.sass";
+
+const Component = () => {
+  return (
+    <div className={styles.foo}>
+      <div className={styles.bar}>Bar</div>
+      <div className={styles.baz}>Baz</div>
+      <div className={styles.active}>Active</div>
+      <div className={styles.child}>Child</div>
+      <div className={styles.sibling}>Sibling</div>
+      <div className={styles.other}>Other</div>
+      <div className={styles.complex}>Complex</div>
+      <div className={styles.compound}>Compound</div>
+      <div className={styles.direct}>Direct</div>
+      <div className={styles.adjacent}>Adjacent</div>
+      <div className={styles.general}>General</div>
+    </div>
+  );
+};
+
+export default Component;
\ No newline at end of file
diff --git a/src/test/suite/CompletionProvider.test.ts b/src/test/suite/CompletionProvider.test.ts
index 419bd35..9e028f8 100644
--- a/src/test/suite/CompletionProvider.test.ts
+++ b/src/test/suite/CompletionProvider.test.ts
@@ -10,6 +10,7 @@ import {
   SAMPLE_TSX_FILE,
   SAMPLE_TS_FILE,
   STYLUS_JSX_FILE,
+  SASS_JSX_FILE,
 } from "../constant";
 import { readOptions } from "../utils";
 
@@ -19,6 +20,7 @@ const uri3 = vscode.Uri.file(SAMPLE_JS_FILE);
 const uri4 = vscode.Uri.file(SAMPLE_TSX_FILE);
 const uri5 = vscode.Uri.file(SAMPLE_TS_FILE);
 const uri6 = vscode.Uri.file(SAMPLE_ASTRO_FILE);
+const uri7 = vscode.Uri.file(SASS_JSX_FILE);
 
 function testCompletion(
   position: vscode.Position,
@@ -210,3 +212,10 @@ test("support astro", () => {
     assert.ok(false, `error in OpenTextDocument ${err}`);
   });
 });
+
+test("support .sass completion", () => {
+  const position = new vscode.Position(4, 27);
+  return Promise.resolve(testCompletion(position, 14, uri7)).catch((err) => {
+    assert.ok(false, `error in OpenTextDocument ${err}`);
+  });
+});
diff --git a/src/utils/index.ts b/src/utils/index.ts
index f352505..1a71eb4 100644
--- a/src/utils/index.ts
+++ b/src/utils/index.ts
@@ -1,4 +1,11 @@
-import { Position, TextDocument, CompletionItem, CompletionItemKind, TextEdit, Range } from "vscode";
+import {
+  Position,
+  TextDocument,
+  CompletionItem,
+  CompletionItemKind,
+  TextEdit,
+  Range,
+} from "vscode";
 import * as fse from "fs-extra";
 import * as _ from "lodash";
 
@@ -12,7 +19,10 @@ export function getCurrentLine(
 /**
  * @TODO Refact by new Tokenizer
  */
-export async function getAllClassNames(filePath: string, keyword: string): Promise<string[]> {
+export async function getAllClassNames(
+  filePath: string,
+  keyword: string
+): Promise<string[]> {
   // check file exists, if not just return []
   const filePathStat = await fse.stat(filePath);
   if (!filePathStat.isFile()) {
@@ -22,10 +32,16 @@ export async function getAllClassNames(filePath: string, keyword: string): Promi
   const content = await fse.readFile(filePath, { encoding: "utf8" });
   let matchLineRegexp = /.*[,{]/g;
 
-   // experimental stylus support
-  if (filePath.endsWith(".styl") ||filePath.endsWith(".stylus")) {
-    matchLineRegexp = /\..*/g
+  // experimental stylus support
+  if (filePath.endsWith(".styl") || filePath.endsWith(".stylus")) {
+    matchLineRegexp = /\..*/g;
   }
+
+  // experimental sass support
+  if (filePath.endsWith(".sass")) {
+    matchLineRegexp = /(^|[\s,&>+~])\.[_A-Za-z0-9-]+/gm;
+  }
+
   const lines = content.match(matchLineRegexp);
   if (lines === null) {
     return [];
@@ -36,7 +52,10 @@ export async function getAllClassNames(filePath: string, keyword: string): Promi
     return [];
   }
 
-  const uniqNames = _.uniq(classNames).map((item) => item.slice(1)).filter((item) => !/^[0-9]/.test(item));
+  const uniqNames = _.uniq(classNames)
+    .map((item) => item.slice(1))
+    .filter((item) => !/^[0-9]/.test(item));
+
   return keyword !== ""
     ? uniqNames.filter((item) => item.indexOf(keyword) !== -1)
     : uniqNames;
@@ -53,19 +72,33 @@ export function dashesCamelCase(str: string): string {
 /**
  * check kebab-case classname
  */
-export function isKebabCaseClassName (className: string): boolean {
-  return className?.includes('-');
+export function isKebabCaseClassName(className: string): boolean {
+  return className?.includes("-");
 }
 
 /**
  * BracketCompletionItem Factory
  */
-export function createBracketCompletionItem (className: string, position: Position): CompletionItem {
-  const completionItem = new CompletionItem(className, CompletionItemKind.Variable);
+export function createBracketCompletionItem(
+  className: string,
+  position: Position
+): CompletionItem {
+  const completionItem = new CompletionItem(
+    className,
+    CompletionItemKind.Variable
+  );
   completionItem.detail = `['${className}']`;
-  completionItem.documentation = "kebab-casing may cause unexpected behavior when trying to access style.class-name as a dot notation. You can still work around kebab-case with bracket notation (eg. style['class-name']) but style.className is cleaner.";
+  completionItem.documentation =
+    "kebab-casing may cause unexpected behavior when trying to access style.class-name as a dot notation. You can still work around kebab-case with bracket notation (eg. style['class-name']) but style.className is cleaner.";
   completionItem.insertText = `['${className}']`;
-  completionItem.additionalTextEdits = [new TextEdit(new Range(new Position(position.line, position.character - 1),
-      new Position(position.line, position.character)), '')];
+  completionItem.additionalTextEdits = [
+    new TextEdit(
+      new Range(
+        new Position(position.line, position.character - 1),
+        new Position(position.line, position.character)
+      ),
+      ""
+    ),
+  ];
   return completionItem;
 }