Objectives <p>Self-concept is underresearched in adults with developmental coordination disorder (DCD), as is the role of diagnosis. Self-concept is linked to wellbeing, which has been shown in previous research to be reduced in DCD. This research aimed to examine the relationships between diagnosis, self-concept, and wellbeing and to explore for the first time the autobiographical memories that underpin self-concept in DCD.</p> Methods <p>Across two novel studies, we examined how adults with DCD define their identities and how this relates to their wellbeing, their memories, and the presence of a diagnosis. Both diagnosed (dDCD) and self-identified (sDCD) adults with DCD and without DCD were recruited (Study 1: dDCD <i>N</i> = 97, sDCD <i>N</i> = 48, non-DCD <i>N</i> = 49; Study 2: dDCD <i>N</i> = 104, sDCD <i>N</i> = 32). An online questionnaire asked participants to describe and rate their identity using ‘I am’ statements and (in Study 2) associated memories. Participants also completed scales of wellbeing and, for Study 2, a scale of motor ability.</p> Results <p>We found no significant differences between dDCD and sDCD groups—both had lower wellbeing scores than the non-DCD group and rated their DCD-related self-concepts and memories as negatively valenced (compared to non-DCD-related aspects of their identity). In both studies, self-concept valence was a significant predictor of well-being scores.</p> Conclusions <p>These finding suggests that self-concept in DCD is a priority area for future research and may be an important target for intervention. Furthermore, these data suggest that an early diagnosis of DCD may not be a protective factor.</p>