How long will he travel there? For a letter sent from other countries to China, it usually need a long time. You should first make sure he will be there when the letter arrives.
Does he has Chinese friend there? If he has, you can send the letter to the place where his friend lives.
I want to send a letter from Russian Federation to my Friend in Chongqing "poste restante" or "general delivery" . If Yes. Can I choose any Post Office or only some of them (from 1703)? or only China Post. What the adress can I write on the envelope: an adress of the Post Office, the postal code? Does the Post Office has a e-mail for the contacts? I wish You and Your family goodluck, health and happiness. Thank You!
Does he has Chinese friend there? If he has, you can send the letter to the place where his friend lives.