Kagaku-ji Temple, Buddhist temple in Akō, Japan

Kagaku-ji is a Sōtō Zen temple in Akō, Hyōgo Prefecture, founded in 1645. Its main hall, rebuilt in 1758, has a ceiling painting of bamboo and a tiger by the artist Gishin Hokkyō, dated 1854. The temple gate was moved here from Akō Castle after the castle was demolished in the Meiji era. The grounds also contain a bell tower, a zazen hall, and the graves of the Asano and Mori lords.

Kagaku-ji was founded in 1645 by Asano Naganao, lord of the Akō domain, as the family temple of the Asano clan, with Shugan Ryūden as founding abbot. After the Asano clan was dispossessed in 1701, the temple stayed tied to the domain: in 1739, on the 37th anniversary of the raid, retainers connected to the former Mori house set up the gishi graves in the grounds. Its mountain gate is the former Shioya gate of Akō Castle, moved here after the castle was demolished in the Meiji era.

Kagaku-ji is the 31st stop on the New Saigoku Thirty-Three Kannon Pilgrimage, whose main image in the Gishi Mokuzō-dō is a Senju Kannon that Ōishi Yoshio is said to have carried during the raid on Kira's residence. It is also the 7th temple of the Setouchi Kannon Reijō circuit. Each 14 December the Akō Gishi Festival brings a rakugo-style recital of the Gishi-den in the main hall and a procession of 47 black cats, recalling Asano Naganori's observance of the ban on cruelty to animals.

Kagaku-ji is about eight minutes on foot from Banshū-Akō Station on the JR Akō Line, at Kariya 1992 in Akō. The grounds are free to enter; the Gishi Treasure Hall and the graves area are ticketed, and photography is not allowed inside the hall. The temple gate is the former Shioya main gate of Akō Castle, moved here in the Meiji era, so its pillars were shortened by about nine centimetres.

The temple's bell, cast in 1797, is called the "bell that does not ring", yet it does ring: the earlier bell was damaged by rioters. During wartime metal collection it was spared because of its link to the Akō rōnin.