what other paper work or Visa do i required to work in China?

You also have to apply for a China work visa to enter and stay in China. The papers needed are:
1. One completely filled out visa application form; all blanks on the application form should be filled in with genuine information;
2. One recently taken 2X2 inch photo showing entire face and without a hat on. Please affix the photo to the application form;
3. Original passport with at least 2 blank visa pages and valid for at least 6 months beyond the date of application;
4. Invitation letter from the Chinese governmental organization authorized by the Chinese Foreign Ministry;
5. The original and one photocopy of Employment License for Aliens issued by the Chinese Ministry of Labor and Social Security, or Foreign Expert's Identity Certificate issued by the Chinese State Bureau of Foreign Experts (the original will be checked and returned to the applicant);
6. Physical Examination Record for Foreigners, if the applicant intends to stay in China for more than 6 months.