The purpose of this study is to explore the symmetrical and asymmetrical features of participation in free conversation between Japanese non-native speakers (NNS), via the quantitative and qualitative analysis of spoken interaction in Japanese by five dyads of foreign students. For the quantitative analysis, a coding system known as initiative-response analysis, based on local turn sequence was used. The data is then analyzed qualitatively by focusing on conversational topic expansion to explore how the aspects of participation are constructed via differing types of interaction. The results show that participants tended to distribute their turns into the three following categories: (1) giving back-channel feedback and/or minimal responses ; (2) providing new information based on the interlocutor's utterance ; (3) asking questions regarding the topic. Furthermore, the distribution patterns of these three categories can be broken down into three different types: "spontaneous-contribution-of-information", "question-and-response" and "response". The combinations of these turn-distribution types reveal both symmetrical\ participation and asymmetrical participation in the sample data. However, interaction between dyads that showed pattern discrepancies (i.e. asymmetrical participation) was similar to that of symmetrical participation, confirming that in general, participation between NNS tends to be symmetrical.