China

There is no requirement of the mandatory use of customs brokers in China. Customs Law of the People's Republic of China and Provisions of the Customs of the People's Republic of China on the Administration of Registration of Customs Declaration Entities (Order No. 221 of the General Administration of Customs) provide that, after registration in the Customs, a consignee or consignor of imported/exported goods shall make customs declaration through its own customs declarers, or entrust it to a customs declaration enterprise which has been registered with the Customs for making declaration through the customs declarers of the enterprise.

Customs Law of the People's Republic of China:
http://english.customs.gov.cn/Statics/644dcaee-ca91-483a-86f4-bdc23695e3c3.html
(English)

Provisions of the Customs of the People's Republic of China on the Administration of Registration of Customs Declaration Entities
(Order No. 221 of the General Administration of Customs):

http://www.customs.gov.cn/customs/302249/302266/302267/356075/index.html
(Chinese)