This study assessed the concurrent and prospective associations between psychosocial adjustment and four humor styles, two of which are adaptive (affiliative, self-enhancing) and two maladaptive (aggressive, self-defeating). Participants were 1,234 adolescents (52% female) aged 11-13 years, drawn from six secondary schools in England. Self-reports of psychosocial adjustment (loneliness, depressive symptomatology, and self-esteem) and humor styles were collected at two time points (fall and summer). In cross-lagged panel analyses, self-defeating humor was associated with an increase in both depressive symptoms and loneliness, and with a decrease in self-esteem. In addition, depressive symptoms predicted an increase in the use of self-defeating humor over time, indicating that these may represent a problematic spiral of thoughts and behaviors. Self-esteem was associated with an increase in the use of affiliative humor over the school year but not vice-versa. These results inform our understanding of the ways in which humor is associated with psychosocial adjustment in adolescence.