[3] Originally, Khlong San District was called Bang Lamphu Lang, until 1916 during the King Vajiravudh's reign, when it was part of Thonburi Province.

It became part of Bangkok after the merging of Thonburi and Phra Nakhon Provinces in 1971.

[4] The intersection of Charoen Nakhon and Charoen Rat Roads (Chanroen Rat junction), used to be the location of Pak Khlong San railway station, the terminus of the Maeklong railway line since 1904.

In 1961, when Bangkok was expanding, the government demolished the station and tracks to create Charoen Rat Road.

[5] Khlong San has an area of 6.87 km2 (2.65 mi2), regarded as the middle part of the district.