The building was originally a temple called Myokan-ji Temple, which was established in 720, and was reconstructed in 1395 as Unryu-ji Temple. Unryu-ji Temple is said to have been the family temple of Naganori, the eldest son of Kanamori Nagachika, who was killed in the Honnoji Incident, and the building is said to have been renovated by Nagachika around 1590.

Shoro-mon of Unryu-ji Temple remained even after the Great Fire of 1729, leaving only burn marks on some parts of the clapboards.

The structure is considered to have originally been a shoro-mon of the temple, due to its elements such as a roban (a dew basin at the bottom of a pagoda finial) and a hoju (sacred gem) on the summit of the gently slanting roof, gate grooves formed around the upper layer, and both sides of the central aisle being rolled inwards. According to the “Takayama-shi Jiin Yuishoki,” the building called “Kouunkaku” in Takayama Castle was handed down from Kanamori Nagachika in 1601, and this has come to serve as shoro-mon.