Impaired positive autobiographical memory (AM) is closely linked to emotional disorders. AM impairments are often found in depressed adults and may be related to thedifficulties such persons have in regulating their dysphoric mood. By contrast, less is known about AM disturbances among adolescents, or about the functional relationship of AM disturbances to early-onset depression. A high-risk family design served to compare four groups of youth who differed in depression histories and familial depression risk. Thirty-one currently depressed probands, 185 remitted probands, 204 never-depressed siblings of probands, and 180 healthy control youth were induced into a negative mood prior to recalling positive AMs via a novel memory elicitation procedure. Several positive AM characteristics were assessed. Relative to control youth, unaffected siblings and probands exhibited consistently impaired positive AMs. Moreover, wealso found some evidence that probands were more impaired than siblings, who were in turn more impaired than controls, consistent with a gradient effect. Positive AM disturbances may not only precede the onset of depression in vulnerable youth, but also continue to persist after remission of a depressive episode. Clinical and basic research implications of the findings are discussed. Positive AM impairments may betrait-like, persist in the euthymic phase of depression, and may serve as a risk marker for early-onset depression among vulnerable adolescents. Disturbances in positive AM may negatively impact the mood-regulatory functions of positive memory recall and contribute to persistent sadness and anhedonia, which are core features of depression. Our sample of currently depressed youth was relatively small, tempering ourconclusions. Although we collected data on some important covariates (e.g., socioeconomic status), we lacked information on other relevant variables such as youths' executive functioning orIQ.