Zhoukou (Chinese: 周口; pinyin: Zhōukǒu; Wade–Giles: Chou-k’ou; postal: Chowkow) is a prefecture-level city in eastern Henan province, China. It borders Zhumadian to the southeast, Xuchang and Luohe to the west, Kaifeng to the northwest, Shangqiu to the northeast, and the province of Anhui on all other sides. Its population was 8,953,793 inhabitants at the 2010 census whom 535,738 lived in the built-up (or metro) made up of Chuanhui district and the northern part of Shangshui county.