Renge-in Tanjō-ji (蓮華院誕生寺) is a Buddhist temple of the Shingon Risshu, or Shingon-Vinaya Buddhism, in Tamana, Kumamoto Prefecture. It is the head temple of the Shingon Ritsu school in Kyūshū and a branch temple of Saidai-ji (西大寺) in Nara (奈良). It venerates Mahābodhisattva Kōen as its patron deity. The temple stands on the site of Jōkō-ji Renge-in which was founded either at the end of the Heian period or the beginning of the Kamakura period and burnt down during the wars of the Sengoku period. The first abbot Zeshin Kawahara was instructed through a spiritual communication by Kōen to restore Jōkō-ji Renge-in, which he accomplished in 1930 and renamed it Renge-in Tanjō-ji in honor of the fact that it stands on the birthplace of Kōen.

Kumamoto Prefecture is a prefecture of Japan located on the island of Kyūshū. Kumamoto Prefecture has a population of 1,748,134 and has a geographic area of 7,409 square kilometres (2,861 sq mi). Kumamoto Prefecture borders Fukuoka Prefecture to the north, Ōita Prefecture to the northeast, Miyazaki Prefecture to the southeast, and Kagoshima Prefecture to the south.