The Seibu Sayama Line (西武狭山線, Seibu Sayama-sen) is a commuter railway line in Saitama Prefecture, Japan, operated by the private railway operator Seibu Railway.

The 4.2 km (2.6 mi) line extends from Nishi-Tokorozawa Station on the Seibu Ikebukuro Line to Seibukyūjō-mae Station in Tokorozawa, Saitama.

Limited Express (特急, Tokkyū) (LE) :Ikebukuro to Seibu Chichibu, trains named Chichibu (ちちぶ), Musashi (むさし), with supplementary limited express charge.

The line and its two stations opened on 1 May 1929,[1] initially electrified at 1,200 V DC.

[citation needed] Station numbering was introduced on all Seibu Railway lines during fiscal 2012, with Seibu Sayama Line stations numbered prefixed with the letters "SI" (part of the Seibu Ikebukuro group of lines).