Siheung Korean: [[WP:IPA for Korean|ɕihɯŋ]] is a city in Gyeonggi Province, South Korea.

In the early Three Kingdoms period, the Siheung area was part of the Baekje kingdom. It was lost to Goguryeo along with the Han River valley in 475.

Siheung acquired its current administrative identity on January 1, 1989, when the old county of Siheung was divided into the cities of Siheung, Gunpo, and Uiwang. At the time Siheung city had a population of only 93,000. This number more than tripled in the following decade, as massive suburban apartment complexes were developed.

Notable landmarks include Oi Island, Mount Sorae, and the port and inlet of Wolgot. Siheung includes two new cities that were developed in the 1990s, Sihwa and Wolgot New City. The new city of Sihwa includes a very large industrial complex. Companies headquartered there include Hansung Machinery Co. Korea Polytechnic University established in 1997, and also Kyonggi Institute of Technology established in 1998.

In 2006, Korea Polytechnic University built TIP (Techno Innovation Park). The building has 18 floors used for studying, research, and development for students, faculty, companies and government.