龍華院, Buddhist temple in Kofu, Japan.

Ryūge-in is a Sōtō Zen temple on a hill west of the Kamisone settlement in southern Kofu, with the mountain name Kikokuzan and Shakyamuni as its main image. The temple grounds stand above the Nakamichi-ōkan, the old road linking Kai and Suruga, and the temple is reached from that route.

According to temple tradition, Ryūgein was originally a Shingon temple called Daishōji in the Sakaigawa area of Fuefuki. In the Kamakura period, Ikan moved it to its present site on the hill above Kamisone. It declined, then in the Sengoku period Shōun Dōkei invited Keisetsu Sōshō, a dharma heir of Unchū Sōryū of Kōgon-in, to revive it as a Sōtō Zen temple and renamed it Ryūgein.

The Soto Zen temple's name gave rise to the poetic theme "Ryūge suigetsu" (dragon flower, water moon), one of the Kai Hakkei, eight celebrated views of Kai chosen in the Kyōhō era under Kōfu lord Yanagisawa Yoshisato. The court noble Mushanokōji Sanehide composed a waka on it, and the 1752 text Uramikanwa identifies Ryūge-in as the spot the verse describes.

The temple sits near public transportation stations in central Kofu and is accessible by foot or car from various directions. Note that access to certain areas may be restricted during ceremonies, so checking ahead helps ensure a comfortable visit.

The temple holds a copy of the Heart Sutra attributed to Ono no Michikaze, though the Kai Kokushi credits Kibi no Makibi. It also keeps a memorial tablet for Lady Ryugein-in Kiei Chin, said in the temple record to be the wife of Anayama Nobukimi and in the Kokushi his uncle's mother.