Kurzbeschreibung: The aim of this talk is to advance understanding on the specificities of Japanese mathematics lessons from a cultural perspective. A theoretical reflection will be first developed to illustrate a framework and methodology to study the cultural aspect of mathematics teaching and learning by adopting a perspective developed within the Anthropological Theory of the Didactic. Specifically, the concepts of didactic paradigm and didactic model proposed will be discussed in the Japanese cases to characterize mathematics teaching including the cultural elements that are implicitly or explicitly taken into consideration when designing and implementing mathematics lessons. This theoretical reflection will be followed by a presentation of the international comparative study of mathematics lessons between Switzerland and Japan, which clearly exemplifies the existence of specific didactic paradigms and models (e.g., Japanese structured problem-solving lesson) behind the design and implementation of mathematics lessons and their effects on shaping the cultural specificities of mathematics lessons.