is a junction passenger railway station located in the city of Tokorozawa, Saitama, Japan, operated by the private railway operator Seibu Railway.
Nishi-Tokorozawa Station is served by the Seibu Ikebukuro Line from in Tokyo to , and by its branch, the 4.2 km Seibu Sayama Line to . Nishi-Tokorozawa is located 27.2 km from the terminus of the Seibu Ikebukuro Line at Ikebukuro Station.
The station consists of two ground-level side platforms and one island platform, serving four tracks.
Platforms 1 and 2 are bidirectional platforms used by Sayama Line services, and platforms 3 and 4 are used by Seibu Ikebukuro Line services. Through trains in the up direction from the Sayama Line to Ikebukuro normally use platform 1.
The station opened on 15 April 1915 as . It was renamed Nishi-Tokorozawa on 1 September 1915.
Station numbering was introduced on all Seibu Railway lines during fiscal 2012, with Nishi-Tokorozawa Station becoming "SI18".
Through-running to and from and via the Tokyu Toyoko Line and Minatomirai Line commenced on 16 March 2013.
In fiscal 2019, the station was the 40th busiest on the Seibu network with an average of 25,720 passengers daily.
The passenger figures for the station in previous years are as shown below.