Academic competence beliefs have been widely studied. However, conceptual and measurement efforts have not yet been directed toward understanding perceived underachievement (feeling that one's accomplishments fall below perceived capability). We conducted two studies in order to develop and examine validity evidence for the Perceived Academic Underachievement Scale (PAUS). Participants were individuals enrolled for credit in at least one post-secondary course. In Study 1, we evaluated content validity and conducted an exploratory factor analysis. In Study 2, we conducted a confirmatory factor analysis and investigated external validity. For both samples, PAUS demonstrated good internal consistency reliability, and items loaded strongly onto a single factor. PAUS was empirically distinct from a range of related constructs. Findings represent preliminary validation evidence.