COVID-19 survivors struggle with intense depressive and post-traumatic symptoms in sub-acute stages. Survivor guilt may affect post-acute psychopathology. Herein, we aim to unveil the potential affective mechanism underpinning post-COVID psychiatric implications by focusing on the association of survivor guilt with psychopathology and maladaptive attributional style. At one month after discharge, we evaluated symptoms of depression on The Zung Severity Rating Scale (ZSDS), post-traumatic distress on Impact of Event Scale-Revised (IES-R), and sleep disturbances on the Women’s Health Initiative Insomnia Rating Scale (WHIIRS) in 195 COVID-19 survivors. Interpersonal Guilt Rating Scale (IGRS-15) rated survivor guilt. A discrepancy score between the burden of depression and post-traumatic distress symptoms was computed individually. Dysfunctional depressive attributions were assessed through the Cognition Questionnaire (CQ). Survivor guilt significantly predicts all evaluated psychopathological dimensions. Moreover, higher rates of survivor guilt were associated with an overlap between post-traumatic and depressive symptomatology, thus suggesting that survivor guilt equally sustains both psychiatric manifestations. Finally, survivor guilt fully mediated the relationship between dysfunctional depressive attributions and the discrepancy index. Our results confirm survivor guilt as a clinically relevant form of suffering related to psychopathological dimensions of post COVID-19 infection, gaining the status of a specific phenomenon and a promising treatment target.