It has been represented by David Cheong Kian Young of Pakatan Harapan (PH) since 2023.

The state constituency was created in the 1958 redistribution and is mandated to return a single member to the Selangor State Legislative Assembly under the first past the post voting system.

Ethnic breakdown of Kajang's electorate as of 2023[2] According to the federal gazette issued on 30 March 2018, the Kajang constituency is divided into 21 polling districts.

"Federal Government Gazette - Notice of Contested Election - By-election of the State Legislative Assembly of N.25 Kajang for the State of Selangor [P.U.

"Federal Government Gazette - Notice of Contested Election, State Legislative Assembly for the State of Selangor [P.U.