diff --git a/lib/rules/selector-not-notation/__tests__/index.js b/lib/rules/selector-not-notation/__tests__/index.js
index a7ec2c43dc..3957dc123b 100644
--- a/lib/rules/selector-not-notation/__tests__/index.js
+++ b/lib/rules/selector-not-notation/__tests__/index.js
@@ -5,7 +5,7 @@ const { messages, ruleName } = require('..');
 testRule({
 	ruleName,
 	config: ['simple'],
-	fix: false,
+	fix: true,
 
 	accept: [
 		{
@@ -80,7 +80,7 @@ testRule({
 testRule({
 	ruleName,
 	config: ['complex'],
-	fix: false,
+	fix: true,
 
 	accept: [
 		{
@@ -99,11 +99,19 @@ testRule({
 
 	reject: [
 		{
-			code: ':not(.foo):not(a) {}',
-			fixed: ':not(.foo, a) {}',
+			code: ':not(.foo ,:hover  ):not(  a,div) {}',
+			fixed: ':not(.foo, :hover, a, div) {}',
 			message: messages.expected('complex'),
 			line: 1,
-			column: 11,
+			column: 21,
+		},
+		{
+			code: ':not():not(a) {}',
+			fixed: ':not(a) {}',
+			message: messages.expected('complex'),
+			line: 1,
+			column: 21,
+			skip: true,
 		},
 	],
 });
diff --git a/lib/rules/selector-not-notation/index.js b/lib/rules/selector-not-notation/index.js
index 600256db75..de861028c8 100644
--- a/lib/rules/selector-not-notation/index.js
+++ b/lib/rules/selector-not-notation/index.js
@@ -22,6 +22,8 @@ const meta = { url: 'https://stylelint.io/user-guide/rules/list/selector-not-not
 
 /** @typedef {import('postcss-selector-parser').Node} Node */
 /** @typedef {import('postcss-selector-parser').Selector} Selector */
+/** @typedef {import('postcss-selector-parser').Pseudo} Pseudo */
+/** @typedef {import('postcss-selector-parser').Container} Container */
 
 /**
  * @param {Node} node
@@ -96,10 +98,7 @@ const rule = (primary, _, context) => {
 
 						if (!hasConsecutiveNot) return;
 
-						if (context.fix) {
-							/* TODO */
-							return;
-						}
+						if (context.fix) return fixComplex(/** @type {Pseudo} */ (prev));
 					} else {
 						const selectors = pseudo.nodes;
 
@@ -131,7 +130,7 @@ const rule = (primary, _, context) => {
 };
 
 /**
- * @param {import('postcss-selector-parser').Pseudo} not
+ * @param {Pseudo} not
  */
 function fixSimple(not) {
 	const simpleSelectors = not.nodes
@@ -144,12 +143,13 @@ function fixSimple(not) {
 		});
 
 	not.empty();
+	// @ts-ignore
 	not.nodes.push(simpleSelectors.shift());
 
 	for (const s of simpleSelectors) {
-		const last = not.parent.last;
+		const last = /** @type {Container} */ (not.parent).last;
 
-		not.parent.insertAfter(
+		/** @type {Container} */ (not.parent).insertAfter(
 			last,
 			last.clone({
 				nodes: [s],
@@ -158,6 +158,33 @@ function fixSimple(not) {
 	}
 }
 
+/**
+ * @param {Pseudo} previousNot
+ */
+function fixComplex(previousNot) {
+	const indentAndTrimRight = (/** @type {Selector[]} */ selectors) => {
+		for (const s of selectors) {
+			s.nodes[0].rawSpaceBefore = ' ';
+			s.nodes[0].rawSpaceAfter = '';
+		}
+	};
+	const [head, ...tail] = previousNot.nodes;
+	let node = previousNot.next();
+
+	head.nodes[0].rawSpaceAfter = '';
+	indentAndTrimRight(tail);
+
+	while (isNot(node)) {
+		const selectors = /** @type {Pseudo} */ (node).nodes;
+		const prev = node;
+
+		indentAndTrimRight(selectors);
+		previousNot.nodes = previousNot.nodes.concat(selectors);
+		node = node.next();
+		prev.remove();
+	}
+}
+
 rule.ruleName = ruleName;
 rule.messages = messages;
 rule.meta = meta;