The purpose of this study was to examine associations between multidimensional perfectionism and anxiety across the school year in a sample of first-generation high school students (i.e., neither parent completed post-secondary school). Three competing theoretical models were tested (i.e., the vulnerability model, in which perfectionism predicts increased psychopathology; the scar model, in which psychopathology predicts increased levels of perfectionism; and the reciprocal-causality model, in which perfectionism and psychopathology predict each other over time). The sample included 148 high school students (44% boys) between the ages of 13 and 18 (M = 14.90 years; SD = 1.29) who were surveyed at the beginning and end of the school year. Using a half-longitudinal design with latent cross-lagged analyses, results indicated that greater anxiety predicted higher levels of self-oriented perfectionism over time, after accounting for age, sex, emotional stability, and conscientiousness. Findings support the scar model whereby psychopathology predicts perfectionism in first-generation youth.