本顕寺, Buddhist temple in Kimitsu, Japan.

Honkenji is a Nichiren Shoshu temple on Mount Hoko in Kimitsu, Chiba Prefecture, at 309-1 Sadamoto. Founded in 1328 by Sano Nichigaku as a branch temple of Hota Myohoji, it belongs to the Nikko lineage. The temple returned to Nichiren Shoshu in 2019 after a long dispute over its chief priest.

Founded in 1328 by Sano Anichigaku as a branch temple of Hotta Myōhonji, Honkenji belonged to the Nikko line of Nichiren Buddhism. In 1876 it joined the formation of the Nichiren-shū Kōmon-ha, which became the Honmon-shū in 1899. On 7 April 1957 it merged into Nichiren Shōshū together with Myōhonji and three other branch temples. Its 34th abbot was excommunicated in 1982 but kept occupying the temple; it was returned to Nichiren Shōshū on 24 January 2019, and religious activities resumed that 25 July.

Honkenji belongs to the Nichiren Shoshu school and carries the mountain name Hokosan. It was founded in 1328 by Sano Nichigaku as a branch temple of Hotta Myohoji in the Nikko line. In 1957 it joined Nichiren Shoshu together with Myohoji and three other branch temples.

Honkenji stands at 309-1 Sadamoto, Kimitsu, Chiba Prefecture, about a 5-minute drive from Kimitsu Station on the Uchibo Line or 10 minutes by car from the Kimitsu Interchange of the Tateyama Expressway. The grounds are occupied by the 34th abbot's residence, so religious activities only resumed in 2019; visitors should check before planning a temple visit.

Honkenji's 34th abbot, Sano Endo, was excommunicated in 1982 after rejecting the authority of Nichiren Shoshu's 67th high priest Nikken, yet kept occupying the temple until his death on 12 November 2018. The temple was returned to Nichiren Shoshu on 24 January 2019, and religious services resumed that 25 July.