Background and Objectives: Clinical performance self-efficacy is a key factor influencing learners' readiness to perform clinical tasks and deliver safe, high-quality care. Clinical skills training can enhance this self-efficacy by providing opportunities for practice, feedback, and learning within a supportive environment. Therefore, the overall aim of this study is to investigate the impact of clinical skills training on the clinical performance self-efficacy of postgraduate students and residents at Mazandaran University of Medical Sciences.

Methods: This study was applied in nature and employed a descriptive-survey design. The statistical population consisted of 1,665 postgraduate students and residents at the Mazandaran University of Medical Sciences; a sample of 312 individuals was selected using stratified random sampling based on Cochran's formula. Data were collected using a researcher-developed questionnaire on clinical skills training (40 items) and a questionnaire on clinical performance self-efficacy (37 items). The face and content validity of the instruments were confirmed by experts, and their reliability was assessed using Cronbach's alpha coefficient, yielding values of 0.87 for the clinical skills training questionnaire and 0.90 for the clinical performance self-efficacy questionnaire. Univariate and multivariate regression analyses were used to analyze the data.

Results: Clinical skills training and its dimensions have a positive and significant impact on the clinical performance self-efficacy of graduate students and residents at Mazandaran University of Medical Sciences. Furthermore, the "faculty" dimension—with a beta coefficient of β = 0.491—exerts the greatest influence on the students' clinical performance self-efficacy.

Conclusion: Given that the faculty dimension contributed the most to predicting clinical performance self-efficacy, strengthening the educational and supportive roles of faculty members could be effective in enhancing the self-efficacy of these learners.