Simpang Renggam () is a town and municipality in Kluang District in central Johor, Malaysia. It spans over an area of 1,002.47 km<sup>2</sup>, with town centre in Ulu Benut Mukim.
Simpang Renggam District Council (), formerly Kluang South District Council () until 1 January 2001, is the local authority of Simpang Renggam and other towns of the southern half of Kluang region, including the nearby towns of Renggam and Layang-Layang. The district council was formed on 1 September 1979 through the merger of the six local councils of Renggam, Simpang Renggam, Machap, Layang-Layang, Sungai Sayong and Taman Sri Lambak. Initially headquartered in Renggam, it was relocated to a two storey tall building in Simpang Renggam on 1 January 1996, and later a bigger modernised administrative complex on 21 January 2021 (although the former still serves as a Branch office for the district council).
As of 2025, Simpang Renggam is divided into 24 zones represented by 24 councillors to act as mediators between residents and the district council. The councillors for the 1 April 2024 to 31 December 2025 session are as below:
Simpang Renggam is home to the Johor Prison, which began construction in 1982 and completed in 1986. It has a capacity of 2,500 and includes a moral rehabilitation centre, special rehabilitation centre and a special detention centre.