You need to apply for Chian work visa (Z), you can apply for it 1 or 2 months before your departure, you should submit visa application at least 2 weeks before your departure, otherwise, you won't have enough time to apply for it. The business visa is different from work visa.

For work visa application, you need to have the work permit and visa notification letter from your employer in China.

Hello , the business visa is different from work visa.if you want to apply for a work visa, the process is a little complex. You should begin to do your application more or less one month before you come to China.