Go to https://www.google.com/history and sign in with your Google account. You can see all your web history listed there.
To remove all your web history, enable the check box (see screenshot above) and click ‘Remove all web history’. If you want to keep some of your web history undeleted, you can do that by unselecting the desired history. Then click OK to remove all history from your account.
Please note that, if you choose deleting everything, your web history will also be paused until you reactivate it. You can read more about Google’s new privacy policy from here. (via)
