This study explored the role of group cohesiveness and psychological distance with tour guides in the relationship between customer interactions and conformity intention with other customers’ complaints in a travel group. Surveys were administered to Korean travelers who have experience in overseas package tours. A total of 276 valid responses were collected and analyzed using PROCESS path modeling. The results showed direct and indirect interactions between customers have a direct influence on group cohesiveness, and group cohesiveness also has a direct influence on conformity intention. On the other hand, only direct interactions between customers directly affect conformity intention with other customers’ complaints, and the verification of the mediating effect of group cohesiveness showed that both direct and indirect interactions between customers had an indirect effect on conformity intention by fully mediating group cohesiveness. Finally, the psychological distance with the tour guide was shown to moderate indirect effect of direct interaction between customers on conformity intention by mediating group cohesiveness. The results of this study demonstrate that group cohesiveness and psychological distance with tour guides are critical variables to the group behavior through social interaction among travel group members, suggesting that travel enterprises must consider the role of tour guide in terms of customer cohesion and customer relationship in the travel group.