This study aims to analyse the impact of a four-day inclusive basketball campus on the self-efficacy (SE) of players with or without a disability (pre- vs. post-intervention design). A sample of 44 participants, 23 without a disability and 21 with a physical disability, all wheelchair users, participated in this study. The entire sample formed part of the intervention group participating in the Inclusive Basketball Campus of the Real Madrid Foundation over four days. To measure the SE of the participants, a basketball SE questionnaire was used, evaluating the degree of confidence in the skilled performance that they felt during the games and training sessions. The results suggested that the intervention had an overall positive effect (p < 0.01; [partial eta-squared] = 0.35, large), and the intervention was invariable as regards the factors between the groups (i.e. having a disability and gender). Also, there were significant differences for the disability between-group factor (p < 0.01; [partial eta-squared] = 0.33, large), but not for gender. It is concluded that the inclusive sport campus influence the SE of players with and without disabilities, but those with a disability achieved lower SE scores than those without a disability.