This study aimed to refine and further develop existing motivation scales (i.e., MSSC by Trail and James, 2001; SII by Funk, Mahony, Nakazawa, & Hirakawa, 2001) in a cross-national context, and to examine differences of descriptive variables (e.g., demographics, attendance frequency) and spectator motives between South Korean and Japanese professional soccer spectators. We confirmed that the refined motivation scales we developed were valid and that they reliably measured Korean and Japanese soccer spectators’ motives. We also found that there were several differences in demographics, attendance frequency, team identification, and spectator motives. For example, Korean spectators were significantly higher in motivation related to personal benefits (family, player, and drama) than Japanese ones. Whereas, Japanese spectators were significantly higher in motivation related to the sport (physical skill and entertainment) and self-definition (vicarious achievement and team identification) than Korean spectators.