Simulated patients (SP) contribute to health professional education for communication, clinical skills teaching, and assessment. Although a significant body of literature exists on the involvement of adult SPs, limited research has been conducted on the contribution of children and adolescents. This systematic review, using narrative summary with thematic synthesis, aims to report findings related to children/adolescents as simulated patients in health professions education (undergraduate or post-graduate). A systematic review of qualitative and quantitative literature published between 1980 and September 2014 was undertaken using databases including CINAHL, Ovid Medline and Scopus. The lack of literature related to the employment of children and adolescents in nursing education dictated the expansion of the search to the wider health professions. Key search terms related to the employment of children and adolescents in health professional education programs. A total of 58 studies reduced to 36 following exclusion based on abstract review. Twenty-two studies reached full text review; following application of inclusion and exclusion criteria, 15 English language studies involving children and/or adolescents in simulation formed part of this systematic review. Five key themes emerged: Process related to recruitment, duration and content of training programs, support and debriefing practice, ethical considerations, and effects of participation for key stakeholders such as children and adolescents, parent and faculty, and learner outcomes. The results suggest that the involvement of children and adolescents in simulation for education and assessment purposes is valuable and feasible. The review identified the potential for harm to children/adolescents; however, rigorous selection, training and support strategies can mitigate negative outcomes. The ability of children to portray a role consistently across assessments, and deliver constructive feedback remains ambiguous.