Shugyo, a Japanese term for spiritual exercise or asceticism, is a key term in Religious Studies in Japan. However, it seems difficult to analyze ascetic or meditation practices in established Theravada Buddhism in contemporary Thailand using the term shugyo, especially in the narrow sense of shugyo. On the other hand, in the case of Thammakai or Dhammkaya temple that have newly appeared as a Theravada Buddhist group in Thailand, it is easy to apply the narrow meaning of shugyo to the practice of this temple. This article analyses these two types of religious practices with reference to the term shugyo. For this purpose, at first, the three characteristics of the narrow meaning of shugyo are mentioned. Then the problems of these characteristics are clarified when these are applied to the practices in Theravada Buddhism. Some of the characteristics of shugyo can be applied to the theoretical theme of "Body and Space" in the case of Thammakai temple. However it needs a different point of view to understand the meaning of the broad sense of shugyo, which includes ascetic or meditation practices in established Theravada Buddhism. In order to find this new point of view, the theoretical theme of "Shugyo and Time" are argued with the comparison of ritual and shugyo.
