Gergei is a comune (municipality) in the Province of Cagliari in the Italian region Sardinia, located about 50 kilometres (31 mi) north of Cagliari. As of 31 December 2004, it had a population of 1,413 and an area of 36.1 square kilometres (13.9 sq mi).
Gergei borders the following municipalities: Barumini, Escolca, Gesturi, Isili, Mandas, Serri.