diff --git a/src/browser/tests/node/node.html b/src/browser/tests/node/node.html
index 9305bf87..72c51748 100644
--- a/src/browser/tests/node/node.html
+++ b/src/browser/tests/node/node.html
@@ -189,3 +189,24 @@
   testing.expectEqual(8, Node.COMMENT_NODE);
   testing.expectEqual(11, Node.DOCUMENT_FRAGMENT_NODE);
 </script>
+
+<div id="rootNodeComposed"></div>
+<script id=getRootNodeComposed>
+  const testContainer = $('#rootNodeComposed');
+  const shadowHost = document.createElement('div');
+  testContainer.appendChild(shadowHost);
+  const shadowRoot = shadowHost.attachShadow({ mode: 'open' });
+  const shadowChild = document.createElement('span');
+  shadowRoot.appendChild(shadowChild);
+
+  testing.expectEqual('ShadowRoot', shadowChild.getRootNode().__proto__.constructor.name);
+  testing.expectEqual('ShadowRoot', shadowChild.getRootNode({ composed: false }).__proto__.constructor.name);
+  testing.expectEqual('HTMLDocument', shadowChild.getRootNode({ composed: true }).__proto__.constructor.name);
+  testing.expectEqual('HTMLDocument', shadowHost.getRootNode().__proto__.constructor.name);
+
+  const disconnected = document.createElement('div');
+  const disconnectedChild = document.createElement('span');
+  disconnected.appendChild(disconnectedChild);
+  testing.expectEqual('HTMLDivElement', disconnectedChild.getRootNode().__proto__.constructor.name);
+  testing.expectEqual('HTMLDivElement', disconnectedChild.getRootNode({ composed: true }).__proto__.constructor.name);
+</script>
diff --git a/src/browser/webapi/Node.zig b/src/browser/webapi/Node.zig
index 8e65a5e9..596dc554 100644
--- a/src/browser/webapi/Node.zig
+++ b/src/browser/webapi/Node.zig
@@ -259,14 +259,23 @@ const GetRootNodeOpts = struct {
 };
 pub fn getRootNode(self: *const Node, opts_: ?GetRootNodeOpts) *const Node {
     const opts = opts_ orelse GetRootNodeOpts{};
-    if (opts.composed) {
-        log.warn(.not_implemented, "Node.getRootNode", .{ .feature = "composed" });
-    }
 
     var root = self;
     while (root._parent) |parent| {
         root = parent;
     }
+
+    // If composed is true, traverse through shadow boundaries
+    if (opts.composed) {
+        while (true) {
+            const shadow_root = @constCast(root).is(ShadowRoot) orelse break;
+            root = shadow_root.getHost().asNode();
+            while (root._parent) |parent| {
+                root = parent;
+            }
+        }
+    }
+
     return root;
 }