No because there are no unlocked iPhone 5's for sale in the US at the moment.
You will also have warranty issues and there are no international warranties with the iPhone. You will also have issues with the LTE frequency and the phone will only work on 3G.
If you live in China, then wait until the iPhone 5 becomes available there and buy it there.
If you live in the US and purchase an iPhone 5 on contract there, then you can use the phone in China with the international roaming feature, although you will only be able to get 3G rather than 4G.