There are two major schools persist at present namely Theravada and Mahayana. These two schools presented new concepts to establish their philosophical foundation and the metaphysics. In the history of Buddhist philosophy, it can be seen some controversial statements among the Theravada and Mahayana -Yogācāra schools. One of the most controversial expressions is the concept of bhavaṅga-citta (life-continuum consciousness) of Theravada and ālaya-vijñāna (store-consciousness) of Yogācāra School. Especially, these concepts reveal the psychic process of the human being. Modern scholarship suggests that bhavaṅga -citta and ālaya-vijñāna similar to unconscious state of the mind. However, so far, there seems to be few studies done by modern scholars. But they haven’t paid more attention to the comparative study of the relevant concepts. Therefore, this study attempts to present Early Buddhist analysis of mind, Theravada and Yogācāra definition of consciousness, similarities and differences between bhavaṅga-citta and ālaya-vijñāna which were illustrated in the relevant texts and modern scholar’s interpretations.