This article provides a timely exploration of the relationship between hospitality employee service sabotage and customer deviant behaviors in Taiwan. The authors also examine the mediating role of relational quality and the moderating role of corporate reputation. The proposed research framework was tested using data from 226 customers of casual dining restaurants who responded to a questionnaire-based survey that was administered in northern Taiwan. The results indicate that employee service sabotage is positively related to customer deviant behaviors and potentially increases the incidence of the latter. Moreover, the relationship between employee service sabotage and customer deviant behaviors is mediated by relational quality, including satisfaction and commitment. It was found that the relationship between employee service sabotage and customer deviant behaviors is negatively moderated by corporate reputation. Employee service sabotage has less effect on customer deviant behaviors when customers perceive corporate reputation more positively. The study contributes to knowledge by proposing an empirically developed and tested conceptual model that offers an enhanced understanding of the relationship between employee service sabotage and customer deviant behaviors.