how can i get china visa for business in Bangladesh?

First, you have to ask your business partner or host unit in China to send you an official invitation letter issued by an authorized unit, such as Foreign Affairs Office, then you prepare your passport, fill in visa application form V.2011A and V.2011B, if it is the first time for you to go to Mainland China, please submit the application in person to China embassy in Dhaka. It takes 4 working days for processing.