The way that parents express their emotions during interactions with their adolescent children is important for adolescent adjustment, and predicts adolescent emotional problems such as depression. In the current study, we assessed whether adolescent depressive symptoms were associated with neural activity during exposure to their mother's affective behavior. Thirty adolescents (18 females, mean age 17.35, s.d. 0.43) participated in an fMRI task that used digitized video segments of their own mother's, as well as an unfamiliar mother's affective behavior as stimuli. Exposure to one's own (compared to an unfamiliar) mother's positive (compared to neutral) behavior was associated with activation in the anterior and posterior cingulate, precuneus and ventrolateral prefrontal cortex. In contrast, exposure to positive behavior across own and an unfamiliar mother (controlling for neutral behavior) was associated with superior temporal sulcus, occipital pole, amygdala and striatum activity. Adolescent depressive symptoms were associated with reduced rostral anterior cingulate activity during exposure to one's own (compared to an unfamiliar) mother's positive behavior, and reduced striatal activity during exposure to positive behavior in general. This study represents an important step in furthering our understanding of the neural basis of affective processing in adolescents. Further, the results support a disruption of reward function in depression.