I wish to marry my fiancee in China, what documents will i need to prove i am single?

You need a Single Status Certificate which is issued by local "Births, Deaths and Marriages Registration". If you has got married in the past, you are advised to present a death certificate of the past spouse, a divorce certificate or a court degree nisi of dissolution of marriage. All the above mentioned documents should be duly authenticated by Australian Department of Foreign Affairs and Trade or its representative offices in various states, before they can be further authenticated by the Consular Section of this Embassy.

When you apply for authentication of Single Status Certificate at the embassy or consulate, you can apply for a China tourist visa at the same time.