In the winter of 1941, Ma Buqing, a follower of the warlord Ma Bufeng, came to seek treasure around the Mogao Grottoes and found a pottery pagoda( the Tianxi Pagoda) and a stele recording the construction of the pagoda(Record of Tianxi Pagoda). These two cultural relics are the remnants of a Buddhist stupa built in the third year of the Tianxi era of the Northern Song dynasty, which, combined with the presence of inscriptions with exact dates on both items, makes them very important physical material for studying later Dunhuang Buddhism. This paper presents a study on the excavation site and the details of these items.