Music self-concept integrates perceptions, beliefs, and self-schemas about a person’s musical abilities and potential. Like other self-concept dimensions, it is multifaceted, hierarchically organized and has implications for motivation toward musical practice. The Music Self-Perception Inventory (MUSPI) is a theoretically based instrument assessing six specific music self-concept dimensions, as well as global music self-concept. Nonetheless, its applicability is limited by its length (84 items). In this study, we developed and validated a 28-item short form of the MUSPI, and showed that the short form yielded equivalent psychometric properties as the original. We validated the original MUSPI on a first sample and used these results to develop a shorter version (MUSPI-S), which we then cross-validated using a new independent sample. We also tested whether the MUSPI-S psychometric properties generalized (were invariant) across gender and grade-differentiated subgroups. Finally, we examined the convergent validity of the MUSPI and MUSPI-S. Results highlighted the psychometric soundness of the MUSPI-S on all criteria, and showed that it presented patterns of associations with other constructs equivalent to those observed with the original MUSPI.