diff --git a/lib/checks/aria/required-children.js b/lib/checks/aria/required-children.js
index 6d61ef5db5..73e30dd1e3 100644
--- a/lib/checks/aria/required-children.js
+++ b/lib/checks/aria/required-children.js
@@ -3,7 +3,7 @@ implicitNodes = axe.commons.aria.implicitNodes,
 matchesSelector = axe.commons.utils.matchesSelector,
 idrefs = axe.commons.dom.idrefs;
 
-function owns(node, role, ariaOwned) {
+function owns(node, virtualTree, role, ariaOwned) {
 	if (node === null) { return false; }
 	var implicit = implicitNodes(role),
 	selector = ['[role="' + role + '"]'];
@@ -13,9 +13,8 @@ function owns(node, role, ariaOwned) {
 	}
 
 	selector = selector.join(',');
-
-	return ariaOwned ? (matchesSelector(node, selector) || !!node.querySelector(selector)) :
-		!!node.querySelector(selector);
+	return ariaOwned ? (matchesSelector(node, selector) || !!axe.utils.querySelectorAll(virtualTree, selector)[0]) :
+		!!axe.utils.querySelectorAll(virtualTree, selector)[0];
 }
 
 function ariaOwns(nodes, role) {
@@ -23,7 +22,8 @@ function ariaOwns(nodes, role) {
 
 	for (index = 0, length = nodes.length; index < length; index++) {
 		if (nodes[index] === null) { continue; }
-		if (owns(nodes[index], role, true)) {
+		let virtualTree = axe.utils.getFlattenedTree(nodes[index]);
+		if (owns(nodes[index], virtualTree, role, true)) {
 			return true;
 		}
 	}
@@ -39,7 +39,7 @@ function missingRequiredChildren(node, childRoles, all) {
 
 	for (i = 0; i < l; i++) {
 		var r = childRoles[i];
-		if (owns(node, r) || ariaOwns(ownedElements, r)) {
+		if (owns(node, virtualNode, r) || ariaOwns(ownedElements, r)) {
 			if (!all) { return null; }
 		} else {
 			if (all) { missing.push(r); }
diff --git a/test/checks/aria/required-children.js b/test/checks/aria/required-children.js
index 57cdb5046c..46296572c4 100644
--- a/test/checks/aria/required-children.js
+++ b/test/checks/aria/required-children.js
@@ -2,6 +2,7 @@ describe('aria-required-children', function () {
 	'use strict';
 
 	var fixture = document.getElementById('fixture');
+	var shadowSupported = axe.testUtils.shadowSupport.v1;
 
 	var checkContext = {
 		_data: null,
@@ -10,97 +11,141 @@ describe('aria-required-children', function () {
 		}
 	};
 
+	function checkSetup (html, options, target) {
+		fixture.innerHTML = html;
+		axe._tree = axe.utils.getFlattenedTree(fixture);
+		var node = fixture.querySelector(target || '#target');
+		var virtualNode = axe.utils.getNodeFromTree(axe._tree[0], node);
+		return [node, options, virtualNode];
+	}
+
 	afterEach(function () {
 		fixture.innerHTML = '';
+		axe._tree = undefined;
 		checkContext._data = null;
 	});
 
 	it('should detect missing sole required child', function () {
-		fixture.innerHTML = '<div role="list" id="target"><p>Nothing here.</p></div>';
-		var node = fixture.querySelector('#target');
-		assert.isFalse(checks['aria-required-children'].evaluate.call(checkContext, node));
+		var params = checkSetup('<div role="list" id="target"><p>Nothing here.</p></div>');
+
+		assert.isFalse(checks['aria-required-children'].evaluate.apply(checkContext, params));
+		assert.deepEqual(checkContext._data, ['listitem']);
+	});
+
+	(shadowSupported ? it : xit)
+	('should detect missing sole required child in shadow tree', function () {
+		fixture.innerHTML = '<div id="target" role="list"></div>';
+
+		var target = document.querySelector('#target');
+		var shadowRoot = target.attachShadow({ mode: 'open' });
+		shadowRoot.innerHTML = '<p>Nothing here.</p>';
+
+		var tree = axe._tree = axe.utils.getFlattenedTree(fixture);
+		var virtualTarget = axe.utils.getNodeFromTree(tree[0], target);
+
+		var params = [target, undefined, virtualTarget];
+		assert.isFalse(checks['aria-required-children'].evaluate.apply(checkContext, params));
 		assert.deepEqual(checkContext._data, ['listitem']);
 	});
 
 	it('should detect multiple missing required children when one required', function () {
-		fixture.innerHTML = '<div role="grid" id="target"><p>Nothing here.</p></div>';
-		var node = fixture.querySelector('#target');
-		assert.isFalse(checks['aria-required-children'].evaluate.call(checkContext, node));
+		var params = checkSetup('<div role="grid" id="target"><p>Nothing here.</p></div>');
+
+		assert.isFalse(checks['aria-required-children'].evaluate.apply(checkContext, params));
+		assert.deepEqual(checkContext._data, ['rowgroup', 'row']);
+	});
+
+	(shadowSupported ? it : xit)
+	('should detect missing multiple required children in shadow tree when one required', function () {
+		fixture.innerHTML = '<div role="grid" id="target"></div>';
+
+		var target = document.querySelector('#target');
+		var shadowRoot = target.attachShadow({ mode: 'open' });
+		shadowRoot.innerHTML = '<p>Nothing here.</p>';
+
+		var tree = axe._tree = axe.utils.getFlattenedTree(fixture);
+		var virtualTarget = axe.utils.getNodeFromTree(tree[0], target);
+
+		var params = [target, undefined, virtualTarget];
+		assert.isFalse(checks['aria-required-children'].evaluate.apply(checkContext, params));
 		assert.deepEqual(checkContext._data, ['rowgroup', 'row']);
 	});
 
 	it('should detect multiple missing required children when all required', function () {
-		fixture.innerHTML = '<div role="combobox" id="target"><p>Nothing here.</p></div>';
-		var node = fixture.querySelector('#target');
-		assert.isFalse(checks['aria-required-children'].evaluate.call(checkContext, node));
+		var params = checkSetup('<div role="combobox" id="target"><p>Nothing here.</p></div>');
+		assert.isFalse(checks['aria-required-children'].evaluate.apply(checkContext, params));
 		assert.deepEqual(checkContext._data, ['listbox', 'textbox']);
 	});
 
 	it('should detect single missing required child when all required', function () {
-		fixture.innerHTML = '<div role="combobox" id="target"><p role="listbox">Nothing here.</p></div>';
-		var node = fixture.querySelector('#target');
-		assert.isFalse(checks['aria-required-children'].evaluate.call(checkContext, node));
+		var params = checkSetup('<div role="combobox" id="target"><p role="listbox">Nothing here.</p></div>');
+		assert.isFalse(checks['aria-required-children'].evaluate.apply(checkContext, params));
 		assert.deepEqual(checkContext._data, ['textbox']);
 	});
 
 	it('should pass all existing required children when all required', function () {
-		fixture.innerHTML = '<div role="combobox" id="target"><p role="listbox">Nothing here.</p><p role="textbox">Textbox</p></div>';
-		var node = fixture.querySelector('#target');
-		assert.isTrue(checks['aria-required-children'].evaluate.call(checkContext, node));
+		var params = checkSetup('<div role="combobox" id="target"><p role="listbox">Nothing here.</p><p role="textbox">Textbox</p></div>');
+		assert.isTrue(checks['aria-required-children'].evaluate.apply(checkContext, params));
+	});
+
+	(shadowSupported ? it : xit)
+	('should pass all existing required children in shadow tree when all required', function () {
+		fixture.innerHTML = '<div role="combobox" id="target"></div>';
+
+		var target = document.querySelector('#target');
+		var shadowRoot = target.attachShadow({ mode: 'open' });
+		shadowRoot.innerHTML = '<p role="listbox">Nothing here.</p><p role="textbox">Textbox</p>';
+
+		var tree = axe._tree = axe.utils.getFlattenedTree(fixture);
+		var virtualTarget = axe.utils.getNodeFromTree(tree[0], target);
+
+		var params = [target, undefined, virtualTarget];
+		assert.isTrue(checks['aria-required-children'].evaluate.apply(checkContext, params));
 	});
 
 	it('should pass one indirectly aria-owned child when one required', function () {
-		fixture.innerHTML = '<div role="grid" id="target" aria-owns="r"></div><div id="r"><div role="row">Nothing here.</div></div>';
-		var node = fixture.querySelector('#target');
-		assert.isTrue(checks['aria-required-children'].evaluate.call(checkContext, node));
+		var params = checkSetup('<div role="grid" id="target" aria-owns="r"></div><div id="r"><div role="row">Nothing here.</div></div>');
+		assert.isTrue(checks['aria-required-children'].evaluate.apply(checkContext, params));
 	});
 
 	it('should not break if aria-owns points to non-existent node', function () {
-		fixture.innerHTML = '<div role="grid" id="target" aria-owns="nonexistent"></div>';
-		var node = fixture.querySelector('#target');
-		assert.isFalse(checks['aria-required-children'].evaluate.call(checkContext, node));
+		var params = checkSetup('<div role="grid" id="target" aria-owns="nonexistent"></div>');
+		assert.isFalse(checks['aria-required-children'].evaluate.apply(checkContext, params));
 	});
 
 	it('should pass one existing aria-owned child when one required', function () {
-		fixture.innerHTML = '<div role="grid" id="target" aria-owns="r"></div><p id="r" role="row">Nothing here.</p>';
-		var node = fixture.querySelector('#target');
-		assert.isTrue(checks['aria-required-children'].evaluate.call(checkContext, node));
+		var params = checkSetup('<div role="grid" id="target" aria-owns="r"></div><p id="r" role="row">Nothing here.</p>');
+		assert.isTrue(checks['aria-required-children'].evaluate.apply(checkContext, params));
 	});
 
 	it('should pass one existing required child when one required', function () {
-		fixture.innerHTML = '<div role="grid" id="target"><p role="row">Nothing here.</p></div>';
-		var node = fixture.querySelector('#target');
-		assert.isTrue(checks['aria-required-children'].evaluate.call(checkContext, node));
+		var params = checkSetup('<div role="grid" id="target"><p role="row">Nothing here.</p></div>');
+		assert.isTrue(checks['aria-required-children'].evaluate.apply(checkContext, params));
 	});
 
 	it('should pass one existing required child when one required because of implicit role', function () {
-		fixture.innerHTML = '<table id="target"><p role="row">Nothing here.</p></table>';
-		var node = fixture.querySelector('#target');
-		assert.isTrue(checks['aria-required-children'].evaluate.call(checkContext, node));
+		var params = checkSetup('<table id="target"><p role="row">Nothing here.</p></table>');
+		assert.isTrue(checks['aria-required-children'].evaluate.apply(checkContext, params));
 	});
 
 	it('should pass when a child with an implicit role is present', function () {
-		fixture.innerHTML = '<table role="grid" id="target"><tr><td>Nothing here.</td></tr></table>';
-		var node = fixture.querySelector('#target');
-		assert.isTrue(checks['aria-required-children'].evaluate.call(checkContext, node));
+		var params = checkSetup('<table role="grid" id="target"><tr><td>Nothing here.</td></tr></table>');
+		assert.isTrue(checks['aria-required-children'].evaluate.apply(checkContext, params));
 	});
 
 	it('should pass direct existing required children', function () {
-		fixture.innerHTML = '<div role="list" id="target"><p role="listitem">Nothing here.</p></div>';
-		var node = fixture.querySelector('#target');
-		assert.isTrue(checks['aria-required-children'].evaluate.call(checkContext, node));
+		var params = checkSetup('<div role="list" id="target"><p role="listitem">Nothing here.</p></div>');
+		assert.isTrue(checks['aria-required-children'].evaluate.apply(checkContext, params));
 	});
 
 	it('should pass indirect required children', function () {
-		fixture.innerHTML = '<div role="list" id="target"><p>Just a regular ol p that contains a... <p role="listitem">Nothing here.</p></p></div>';
-		var node = fixture.querySelector('#target');
-		assert.isTrue(checks['aria-required-children'].evaluate.call(checkContext, node));
+		var params = checkSetup('<div role="list" id="target"><p>Just a regular ol p that contains a... <p role="listitem">Nothing here.</p></p></div>');
+		assert.isTrue(checks['aria-required-children'].evaluate.apply(checkContext, params));
 	});
 
 	it('should return true when a role has no required owned', function () {
-		fixture.innerHTML = '<div role="listitem" id="target"><p>Nothing here.</p></div>';
-		var node = fixture.querySelector('#target');
-		assert.isTrue(checks['aria-required-children'].evaluate.call(checkContext, node));
+		var params = checkSetup('<div role="listitem" id="target"><p>Nothing here.</p></div>');
+		assert.isTrue(checks['aria-required-children'].evaluate.apply(checkContext, params));
 	});
 
 });