diff --git a/atom/browser/web_view/web_view_manager.cc b/atom/browser/web_view/web_view_manager.cc
index 23023e2b1d..c638c18e12 100644
--- a/atom/browser/web_view/web_view_manager.cc
+++ b/atom/browser/web_view/web_view_manager.cc
@@ -80,16 +80,18 @@ void WebViewManager::AddGuest(int guest_instance_id,
 }
 
 void WebViewManager::RemoveGuest(int guest_instance_id) {
+  if (!ContainsKey(web_contents_map_, guest_instance_id)) {
+    return;
+  }
+
   auto web_contents = web_contents_map_[guest_instance_id].web_contents;
 
-  if (web_contents) {
-    content::BrowserThread::PostTask(
-        content::BrowserThread::IO, FROM_HERE,
-        base::Bind(
-            &WebViewRendererState::RemoveGuest,
-            base::Unretained(WebViewRendererState::GetInstance()),
-            web_contents->GetRenderProcessHost()->GetID()));
-  }
+  content::BrowserThread::PostTask(
+      content::BrowserThread::IO, FROM_HERE,
+      base::Bind(
+          &WebViewRendererState::RemoveGuest,
+          base::Unretained(WebViewRendererState::GetInstance()),
+          web_contents->GetRenderProcessHost()->GetID()));
 
   web_contents_map_.erase(guest_instance_id);