Mr.sikander azam, you should get the invitation letter from the training center, the confirmation letter from your company to prove that you come to Beijing for traning course, you also need to prepare the following documents:
(I) Fully completed Visa Application Form in Chinese or English, attached with one of the applicant's recent color photograph (30mm X 40mm)

(II) Original passport with validity more than six months and minimum 2 blank visa pages;

(III) Photocopy of the first 2 pages (personal information) of the passport and the recent Chinese visa page if there is any;