735000。 According to the query of postal code database network, China adopts four-level six-digit coding system, and the postal code of Suzhou District of Jiuquan City is 735000. Jiuquan, formerly known as Suzhou, is a prefecture-level city under the jurisdiction of Gansu Province, People's Republic of China (PRC). It is located in the northwest of Gansu Province, with a border area of192,000 square kilometers, accounting for 42% of the area of Gansu Province.