Reishi-ji, Buddhist temple in Sanuki, Japan

Reishi-ji is a temple of the Kōyasan Shingon school in Sanuki, Kagawa Prefecture, with the mountain name Nichinai-zan. Its main image is an Eleven-Faced Kannon, and it is the tenth stop on the Sanuki Thirty-Three Kannon pilgrimage. The grounds climb a hillside: the main gate, main hall, Karitei-dō and bell tower stand at the foot, with the Okunoin Daishi-dō and Goma-dō near the top.

According to temple tradition, Kūkai founded the temple during the Kōnin era (810–824) to pray for his teacher Okada Ushikai; it was then called Tōrinzan Henjōkōin or Hiuchizan Taikōji. In 1662 the monk Enin came from Saimei-ji in Yamashiro and sought its revival, and Takamatsu domain lord Matsudaira Yorishige ordered its reconstruction. In 1676 Yoritsune, Yorishige's adopted son and a son of Tokugawa Mitsukuni, renamed it Tōrinzan Reishi-ji and built the main hall.

The temple belongs to the Kōyasan Shingon school and is the tenth stop on the Sanuki Thirty-Three Kannon pilgrimage, whose circuit links it to Enkō-ji 2.3 km away and Jōfuku-ji 41 km away. Its main image is an Eleven-Faced Kannon. Behind the main hall, the graves of two Takamatsu lords, Ienaga and Yorihiro, are set on the hillside.

The temple stands at the foot of a hill in Sanuki, with the main hall, bell tower and Kariatei hall on the lower ground. A path and steps climb past the Matsudaira family memorial chapel to the graves of lords Yoritsune and Yorihiro. The Oku-no-in Daishido near the summit can be reached by car, with parking for a few vehicles.

Behind the main hall, a path climbs the hillside past the grave of Ogawa Hanjiro, a sculptor, and a rock carved with Sanskrit characters (bonji-iwa). Near the summit stand the Oku-no-in Daishi-dō, with parking for a few cars, the Goma-dō and the Gumonji-dō. The temple gate is said to have been moved here from the rear gate of Amataki Castle.