Haimen (, Qihai dialect: , Shanghai: ) is a county-level city under the administration of Nantong, Jiangsu province, with a population of approximately 1 million. It is located at the opposite side of the Yangtze River to Shanghai and is directly north of Chongming Island except for a small portion that forms Haimen City's Haiyong Township.Haimen is the seat of the Roman Catholic Diocese of Haimen.
Haimen is a county-level city of Jiangsu, China.
Haimen may also refer to:
Jiaojiang District, formerly Haimen
- Haimen goat
- Haimen, Guangdong, town in Shantou
- Haimen Town, Jiangsu, seat of Haimen city