This paper first describes the T-shaped cartouches(in both Tibetan and Chinese),and then studies the T-shaped cartouches in the Eight Great Bodhisattvas Mandala painted in Yulin cave 25 to answer three questions: 1.Why did the T-shaped cartouche in the Yulin Cave 25 appear only in the Eight Great Bodhisattvas Mandala? 2.Why was the Tibetan language not used in that cartouche?3.Why was the central Buddha named as "qingjin fasheng lushena fo(Vairocana Buddha)" in the T-shaped cartouche, which is not consistent with the central image of the Manlala？
