The present web-based study (N = 840) aimed to illuminate the cognitive mechanisms underlying self-disorders in autism. Initially, participants selected three self-defining memories. Then, we assessed their capacity to give meaning to these events (i.e., meaning making), their tendency to scrutinize autobiographical memory to better understand themselves (i.e., self-continuity function of autobiographical memory) and their clarity of self-concept. The results showed that individuals with high autistic traits (ATs) had a lower clarity of self-concept than control participants. Meaning making was also reduced in AT individuals and mediated the relation between AT and self-concept clarity. Our results suggest that the reduced clarity of self-concept in AT individuals is related to an impaired capacity to make meaning of important past life events.