The aim of this study was to evaluate mental health and learning disability nursing students' perceptions of the usefulness of the objective structured clinical examination (OSCE) in assessing their administration of medicine competence. Learning disability (n=24) and mental health (n=46) students from a single cohort were invited to evaluate their experience of the OSCE. A 10-item survey questionnaire was used, comprising open- and closed-response questions. Twelve (50%) learning disability and 32 (69.6%) mental health nursing students participated. The OSCE was rated highly compared to other theoretical assessments; it was also reported as clinically real and as a motivational learning strategy. However, it did not rate as well as clinical practice. Content analysis of written responses identified four themes: (i) benefits of the OSCE; (ii) suggestions to improve the OSCE; (iii) concern about the lack of clinical reality of the OSCE; and (iv) OSCE-induced stress. The themes, although repeating some of the positive statistical findings, showed that participants were critical of the university setting as a place to conduct clinical assessment, highlighted OSCE-related stress, and questioned the validity of the OSCE as a real-world assessment. The OSCE has an important role in the development of student nurses' administration of medicine skills. However, it might hinder their performance as a result of the stress of being assessed in a simulated environment.