創建は不詳ですが、戦国時代中期（天文7（1538）年）に平林千眼寺（せんげんじ）の3世底寂玄徹（ていじゃくげんてつ）禅師により、改宗開山した曹洞宗の寺院です。
もとは真言宗で竹林寺（ちくりんじ）と称し、その御本尊であった十一面観世音菩薩を今もお祀りしています。
越後三十三観音霊場の第27番札所となっており、裏山に西国三十三観音霊場より砂を頂いて作った観音様が、33ヵ所あります。
お寺の裏手にある中庭は、裏山を借景に作られた庭園です。

Kojoji is a temple of the Soto sect of Zen Buddhism. The original date of construction is uncertain, but it was converted into a Zen temple by Teijaku Gentetsu, the 3rd Abbot of Sengenji in Hirabayashi, in 1538.
Prior to its conversion, the temple had originally been a Shingon temple named Chikurinji; the main worshiping object of the temple at that time, a beautiful statue of 11-Faced Kannon, is still revered here today.
Kojoji is Stop No. 27 on the “Echigo 33 Kannons” pilgrimage route, and on the mountain behind the temple are 33 shrines to Kannon that were made with sand transported here from the “Saikoku 33 Kannons.”
The courtyard behind the temple was built while taking into consideration the mountain to the rear as a backdrop.