According to "Chokyu-ji engi," in the Nara period, Emperor Shomu ordered Priest Gyoki to found the temple to pay a tribute to a local ruler, Mayumi Takeyumi, who had died by a stray arrow shot by his son.
『長弓寺縁起』によると奈良時代に息子の流れ矢に当たって死んだ豪族・真弓長弓（まゆみたけゆみ）を悼み、聖武天皇が僧・行基に開かせたと伝わる。