Hello, I'm a us citizen wanting to travel to China from lebanon.

Yes, it is required. You should apply for an L type there by providing your passport, a copy of the passport's data page, a completely filled application form glued with a recent personal passport-type photo, the original and photocopy of your entry permit or stay permit for Lebanon, round way tickets and hotel reservations, and a personal bank deposit certificate issued by a local bank showing you have more than 6000 dollars in your account.