Focusing on the Japan-Korea route of the Asian Highway, this paper attempts to investigate the potential Japanese and Korean tourists' touring behavior along the Japan-Korea route in the future when the Asian Highway would be actually operated. This was done by conducting a SP (stated preference) survey in both Japan and Korea, respectively. To represent the observed and unobserved similarities existing among different alternative touring plans, the r_MNL model based on the concept of relative utility is used to represent the observed similarities while the PCL model is used to represent the unobserved similarities. Combining the r_MNL and PCL models results in a new discrete choice model (r_PCL). The effectiveness of the proposed r_PCL model was empirically confirmed. Common and different tourism behaviors between the Japanese and Korean tourists were also clarified.