The subcommentary of the Mahāyānasamgraha is a rare Tang dynasty commentary found in Dunhuang. A transcription is included in the Taishō shinshū daizōkyō, No. 2806. By analyzing its authorship, date, form and philosophical views, this study reaches four conclusions. First, the views expressed in the subcommentary of the Mahāyānasamgraha are similar to those of the southern division of the Dilun school. Second, the style and thought of the subcommentary of the Mahāyānasamgraha are similar to those of Zhiyan; therefore, the author of the subcommentary of the Mahāyānasamgraha might have been a successor to Zhiyan. Third, since Paramārtha's translation of the Mahāyānasamgraha is used as a source text, the subcommentary of the Mahāyānasamgraha can be dated to between the end of the seventh century and the start of the eighth century. It uses the same technical terms as Xuanzang and his disciples; it was therefore most likely written after Xuanzang's translation of the Mahāyānasamgraha, and is contemporaneous with the works of Kuiji and Dunlun. Fourth, many differences exist between T2806 and S.2554: they differ in terms of formula, calligraphy, teaching taxonomy and philosophy. From these differences, we can conclude that they are not the same text.
