The purpose of this study was to investigate the influencing factors on the probability of different types of unplanned eating-out behavior in a tourism destination context. The results indicated that 31.0% of the Japanese tourists consumed specific types foods that they had planned to eat before embarking on travel. The remaining respondents (61%) indicated unplanned eating-out behavior in the form of dropping planned items (21.5%), substituting item (22.1%), adding new item (20.1%), substituting or adding (5.3%). A comparison of pre-travel plans and realized eating-out behavior showed that while travelers developed plans before embarking, these plans frequently were changed depending on various factors. The multinominal logistical analysis reveals that travelers` age, marital status, travel hours to the Busan has a significant influence on the probability of an unplanned eating-out behavior. In addition, the results of binary logistical analysis have shown that store display, sufficient time, good memories of past experiences, preferred taste, travel companion factors played a facilitator`s role influencing on the probability of an unplanned eating-out behavior. Implications and suggestions for future research were discussed.