1. Click the Tools menu, then then select Option.
2. Click the Basics tab.
3. Click the Manage button in the Default search section. The Search Engines dialog box opens.
To add YouTube search engine to google chrome, enter following values:
* Name - YouTube
* Keyword - YouTube
* URL - http://www.youtube.com/results?search_query=%s
More information, visit: How do I add YouTube video search engine to Google Chrome