The tourist-to-tourist encounter is an important topic in tourism business. When people travels abroad, they would have high opportunity to interact directly and indirectly with other tourists. This encounter could end up with encounter conflict negatively or decrease the social distance positively. Consequently, the objective of this research is to investigate the relationship among tourist-to-tourist interactions, role typology, nationality, and tourist’s reaction to encounter. This research concluded that Taiwanese have more experience on encounter conflict than Japanese; higher level of Tourist-to-Tourist encounter could shorten the social distance; and different perception of role play would affect the encounter reaction: conflict and mutual understanding. Finally, the tourist’s role typology moderates the relationship between encounter level and encounter conflict; and the nationality moderates the relationship between encounter level and social distance.