In this book , we deal with the relationship between Japanese Buddhism and the theory of Karmic Retribution. This book consists of 2 chapters. In chapter 1 "Japanese gods and buddhas", we discuss the problem of so-called "syncretization of Shintoism with Buddhism". This syncretization doesn't mean, however, the unification of these two established religions, but the double process in which a foreign religion Buddhism, on the one hand, has developed into Japanese Buddhism in contact with an ancient Japanese faith in native gods and the gods-faith has also been, on the other hand, formed into Shintoism in contact with Buddhism. Consequently Japanese Buddhism was supposed to have a unique feature. In chapter 2