This county was abolished in 1989 as its one town(읍) of Sorae and two townships(면) of Gunja and Suam became Siheung City at the same time.
In 1413, it was rebranded as Geumcheon(금천, 衿川) Prefecture and its name changed again "Siheung" in 1785.
Throughout modern Korean history, many parts of Siheung County were separated or annexed into several administrative districts.
[5] In 1963, Seoul absorbed several Siheung County townships of East (now Geumcheon-gu, Gwanak-gu, and Dongjak-gu) and Sindong (now Seocho-gu),[6] while Hwaseong County's township of Uiwang was absorbed by Siheung[7] and the county office in Yeongdeungpo moved to Anyang township.
In 1973, the township of Anyang separated as Anyang City and Sorae township of Bucheon County, now northern part of Siheung City, was ceded to Siheung County.