The purpose of this article is to find out how motives for learning Japanese were related to Willingness to Communicate in Japanese. The participants were 325 international students who were studying in universities and graduate schools in Japan. The data was collected by two kinds of questionnaires. In the analysis, the structures of international students' motives were examined by using the factor analysis. As a result, five factors were extracted: (1) Interest in studying Japanese; (2) Interest in modern Japanese culture; (3) Orientation of understanding Japan; (4) Incentive orientation; and (5) Instrumental orientation. In addition, the relations between learning Japanese motives and Willingness to Communicate in Japanese were examined by using the path analysis. The result showed that Interest in studying Japanese and Instrumental orientation were related to Willingness to Communicate in Japanese.