Monju-in, Buddhist temple in Matsuyama, Japan

Monju-in is a Shingon Daigo-ha temple in Matsuyama, known as Daihōzan Tokujō-ji. Its main hall enshrines a hidden Monju Bosatsu flanked by two seated Jizō Bosatsu statues, with further unnamed Buddha images along the side bays. Between the main hall and the Henjō-den hall stands the Bishamonten hall, whose image is unveiled on New Year's Day.

Tradition holds that the monk Kūhachi, founder of Saizan Kōryū-ji, first established a temple called Tokujō-ji in the hills here. In 824 the monk Kūkai (Kōbō Daishi) is said to have stayed on the site, guided by Monju Bosatsu, and renamed it Monju-in. The temple later moved to the present grounds, the former estate of the wealthy farmer Emon Saburō, whose eight-year, twenty-one-circuit pilgrimage in search of Kūkai is regarded as the origin of the Shikoku henro.

The temple is the ninth stop on the Shikoku Bekkaku 20 Sacred Sites pilgrimage and also a bangai site of the 88-temple route; its halls hold Jizō Bosatsu and Monju Bosatsu as main images. Bishamonten, one of the seven deities of good fortune venerated in Iyo, is enshrined in a hall between the main hall and the Daishidō, and his image is shown on New Year's Day. The temple is also the birthplace of the Shikoku pilgrimage tradition, tied to the layman Kōno Emon Saburō.

Monju-in stands in the north-west of Matsuyama, with the Hachitsuka burial mounds and the Hachikubo hollows about 1 km to the south-west in the fields and hillside behind the temple. The Bishamonten hall between the main hall and the Daishido opens its image on New Year's Day. The temple is the ninth stop on the Shikoku Bekkaku 20 sacred sites circuit, reached via National Route 11 and Prefectural Route 48.

Behind the temple, in the surrounding fields, stand the Yatsuzuka: eight small mounds said to be the graves of the eight children of Emon Saburo, each topped by a tiny shrine and a stone Jizo. The group is a Matsuyama-designated historic site, registered in 1968.