In this paper, I have discussed the following two points about the study of Abhidharmamahāvibhāṣāśāstra (AMV). Firstly, this study contributes to clarify the relation between the Sarvāstivādin school and a Sūtra in āgamas and nikāyas. Secondly, the study leads to the solution of existential questions in Buddhist practices. First of all, I examined the current status of research on the Abhidharma Buddhism by quantitative analysis using the Indian and Buddhist Studies Treatise Database. This revealed two points as follows: one is a decrease in the number of papers about the Abhidharma Buddhism. The other is that Abhidharmakośa is the primary interest in the Abhidharma studies. Next, I investigated a citation in AMV and compared it with Samyukta-Āgama (SĀ)No. 282. It is clear that SĀ No. 282 is similar to the citation. This means that the study of AMV helps clarify the relation between the Sarvāstivādin school and a Sūtra in āgamas and nikāyas. Finally, I mentioned that the study of AMV contributed to understanding current Buddhist practices. For example, antara-bhāva and tri-śaraṇa are the key concepts of Buddhist rituals. I pointed out that definitions of them in AMV formed the basis of actual Buddhist rituals.
