Rikyū Hachiman-gū, Shinto shrine in Ōyamazaki, Japan

Rikyū Hachiman-gū is a Shinto shrine in Ōyamazaki, Kyoto Prefecture, on the site of Emperor Saga's former Kayō Detached Palace. Its present honden, hieiden and haiden were rebuilt in 1879 and reworked in 1929 into a connected Hachiman-zukuri arrangement. The precinct keeps the Ishiyama well, whose spring prompted the shrine's founding, plus the stone base of a lost tahōtō and a chōzuya from the early Shōwa era.

According to shrine tradition, in 859 the monk Gyōkyō saw a divine light at Mount Kōjin and found a spring at this spot on the Saigoku road; Emperor Seiwa then ordered a shrine built here and named it Iwashimizu Hachiman-gū. In 860 the deity was moved across the Yodo River to Mount Otoko, but a branch remained here. In 1697 the shrine lost the right to use the name Iwashimizu and was formally renamed Rikyū Hachiman-gū. In 1864 the Hamaguri Gate fighting burned most of the buildings except the main gate and east gate.

The shrine's name comes from the Kaya Detached Palace of Emperor Saga, which once stood on this site. Its deity is honoured as the ancestor of oil, and the Hino-tō-sai rite on 3 April recalls the oil-makers' tradition. The grounds also hold a stone where Sugawara no Michizane is said to have sat.

The shrine is a one-minute walk from JR Yamazaki Station on the Tōkaidō Main Line and about three minutes from Hankyū Ōyamazaki Station. The precinct shrank over time: the west side was ceded to Osaka Prefecture after the Meiji separation of Shinto and Buddhism, and the north side was taken for the Tōkaidō Main Line in 1876. The main hall, worship hall and gate stand close together, with the Sotomon (south gate) and East Gate surviving the 1864 fire.

The shrine's name was once contested: a 1697 ruling barred it from using "Iwashimizu Hachiman-gū", the name it had shared with the shrine across the river on Otokoyama, and it has been Rikyū Hachiman-gū officially since. Its oil-seller guild, the Ōyamazaki Aburadza, held the nationwide sales right for egoma oil.