Although authentic leadership might reduce followers’ bad behaviors, scholars have rarely included followers’ workplace deviance as an outcome in their research models. Drawing from authentic leadership and social identity theory, we investigate how authentic leadership decreases followers’ interpersonal deviance. First, we test the mediating role of followers’ social identification in the relationship between authentic leadership and followers’ interpersonal deviance. Second, we consider followers’ perceptions of trust toward their coworkers as one situational factor that influences the relationship between social identification and followers’ interpersonal deviance. Using data from 242 respondents in several business organizations located in Korea, we found that followers’ social identification mediates the relationship between authentic leadership and followers’ interpersonal deviance. Furthermore, followers’ trust toward coworkers (i.e., trust in group) moderates the relationship between social identification and followers’ interpersonal deviance. The theoretical implications, managerial implications and future research directions are discussed.