Depression is the leading cause of disability worldwide1. Early life stress exposure increases risk for depression2 and has been proposed to sensitize the maturing psychophysiological stress system to stress in later life3. In response to stress, positive memory activation has been found to dampen cortisol responses and improve mood in humans4 and to reduce depression-like behaviour in mice5. We used path modelling to examine whether recalling specific positive memories predicts reduced vulnerability to depression (high morning cortisol6-9 and negative self-cognitions during low mood10-12) in adolescents at risk due to early life stress (n = 427, age 14 years)8. We found that positive memory specificity was associated with lower morning cortisol and fewer negative self-cognitions during low mood over the course of one year. Moderated mediation analyses demonstrated that positive memory specificity was related to lower depressive symptoms through fewer negative self-cognitions in response to negative life events reported in the one-year interval. These findings indicate that recalling specific positive life experiences may be a resilience factor13 that helps in lowering depressive vulnerability in adolescents with a history of early life stress.