The excavation in Tuyuq Grottoes initiated in 2010 has brought about numerous archaeological finds. In particular, those discovered in Cave 26 on the high platform in the middle of the Western Section are noteworthy. Many wall inscriptions in Old Uighur, as well as Brahmi and Chinese are preserved in the side rooms, releasing important information on the dating and the nature of this cave. They also contribute new data to the fields of history and linguistics. This paper presents an edition and study of all the 29 inscriptions preserved in Room B, most of which are written in Old Uighur, while others in Chinese.