We compared neural and behavioral responses to feedback received during interpersonal interactions within the Prisoner's Dilemma game between adolescents with anxiety disorders (n = 12) and healthy peers (n = 17). Groups differed significantly in neural activation in the medial prefrontal cortex (mPFC), anterior cingulate cortex (ACC), precuneus, insula, and temporoparietal junction (TPJ). Anxious adolescents were also more likely than controls to cooperate after co-player betrayal. Our findings provide evidence that social behavior and related neural activity differs between anxious and healthy adolescents. These findings constitute a step toward elucidating neural correlates of social impairment in anxious youths.