© 2019, © 2019 Informa UK Limited, trading as Taylor & Francis Group. Substantial changes in cognitive-affective self-referential processing occur during adolescence. We studied the behavioral and ERP correlates of self-evaluation in healthy male and female adolescents aged 12–17 (N = 109). Participants completed assessments of depression symptoms and puberty as well as a self-referential encoding task while 128-channel high-density EEG data were collected. Depression symptom severity was associated with increased endorsement of negative words and longer reaction times. In an extreme group analysis, a negative appraisal-bias subsample (n = 28) displayed decreased frontal P2 amplitudes to both positive and negative word stimuli, reflecting reduced early attentional processing and emotional salience. Compared to the positive appraisal-bias subsample (n = 27), the negative appraisal-bias subsample showed reduced LPP to positive words but not negative words, suggesting attenuated sustained processing of positive self-relevant stimuli. Findings are discussed in terms of neural processes associated with ERPs during negative versus positive self-appraisal bias, and developmental implications.