The Keiō Sagamihara Line (京王相模原線, Keiō-sagamihara-sen) is a Japanese railway line operated by the private railway operator Keio Corporation, connecting Hashimoto Station in Sagamihara, Kanagawa Prefecture and Chōfu Station in Chōfu, Tokyo.

Rapid and Semi express services stop at all stations on this line.

The line opened as a one-stop single-track spur from Chōfu to Keiō-Tamagawa on 1 June 1916, electrified at 600 V DC, and was double-tracked on 1 April 1924.

[citation needed] The line was extended (all extensions were electrified dual track) on 1 April 1971, to Keiō-Yomiuri-Land.

[1] Subsequent extensions brought the line to Keiō-Tama-Center (18 October 1974), Minami-Ōsawa (22 May 1988) and Hashimoto (30 March 1990).