South Tambun () is a town and an administrative district (kecamatan) of Bekasi Regency, in West Java, Indonesia. The district covers an area of 37.12 km<sup>2</sup>, and had a population of 417,008 at the 2010 Census and 431,038 at the 2020 Census; the official estimate as at mid 2024 was 450,469, comprising 226,099 males and 224,370 females. The administrative centre is located at the town of Tambun, and the district is sub-divided into one town (kelurahan) - Jatimulya - and nine villages (desa), all sharing a post-code of 17510, as listed below with their areas and their populations as at mid 2024.