Dear Sir, I am indian working in tanzania, can i visit china from tanzania?

you can apply from Chinese embassy there with your documents of work and residence. Regular processing takes 4 working days. Make sure make an appointment in advance for application. For business visit, following documents are required:
a) Qualified original invitation & guarantee letter from you sponsor.
b) Qualified original introduction letter.
c) Round-trip ticket booking and hotel reservation;
d) The original and one photocopy of the business license and certificate of your company.
e) Ay proof of business connection with the inviting company。
f) Photocopy of the invitor's ID/ the host Chinese company's license. (If any)