<p>Parental job loss has a negative impact on family relationships and child development. Yet, less is known about how parental job loss might influence mental health outcomes in adolescents. This study examined the longitudinal associations of parental job loss with mental health in adolescents 1 and 2 years after job loss. The study analyzed longitudinal data from the Adolescent Brain Cognitive Development (ABCD) Study (<i>N</i> = 7181), a longitudinal study of adolescents aged 9–10 years enrolled from June 2016 to October 2018 from 21 sites in the United States. Parental job loss was reported at baseline by the parent. Adolescent mental health outcomes, including anxious depressed, withdrawn, depressed, somatic complaints, social problems, thought problems, attention problems, rule-breaking behaviors, aggressive behaviors, total psychosis symptoms, psychosis severity, mania, and sleep disturbance, were assessed at 1- and 2-year follow-ups. Parental job loss was associated with increased risks of anxious-depressed symptoms (<i>β</i> = 0.09, 95% CI 0.01–0.17), withdrawn depressed symptoms (<i>β</i> = 0.08, 95% CI 0.00–0.16), social problems (<i>β</i> = 0.11, 95% CI 0.03–0.18), aggressive behaviors (<i>β</i> = 0.09, 95% CI 0.02–0.17), mania (<i>β</i> = 0.13, 95% CI 0.05–0.21), and sleep disturbance (<i>β</i> = 0.08, 95% CI 0.00–0.16) in adolescents 1 year later. Some of these associations persisted even 2 years later (i.e., withdrawn, depressed, aggressive behaviors, and mania). Findings suggest that parental job loss may have long-lasting adverse effects on a host of mental health outcomes in adolescents and should be a consideration in assessments of adolescents’ mental health.</p>