I got married to a Chinese woman in the uk. how do i register our marriage in China?

Dean, I am afraid that you may not register your marriage in China again. Your marriage will be acknowledged by Chinese laws as long as it's true and valid. Why can't you register? Because it requires single certificate or divorce paper when you register your marriage at local civil affairs bureau. You can't provide it as long as you got married.

If you plan to use your marriage certificate in PRC, you just need to get your marriage certificate authenticated by Chinese embassy and then get it notarized by Chinese notary office.