People are stigmatized and socially rejected for a range of deviant appearances and behaviors. This includes the social rejection of people who are depressed or have a pessimistic outlook on life. We examined whether being pessimistically biased (i.e., thinking one's risk for negative events is greater than that of one's peers) also leads to social rejection. Two experiments showed that pessimistically biased individuals were less socially accepted and that this lack of acceptance originated in the presumption that pessimistically biased people are also hopeless, sad, and depressed. In general, people are overwhelmingly optimistically biased. This research suggests one potential reason why pessimistically biased people are stigmatized and socially rejected.