Background: Clinical evaluation is one of the main pillars of medical education. The Objective Structured Clinical Examination is one of the commonly adopted practical tools to evaluate clinical and practical skills of medical students. The purpose of the study is to determine validity and reliability of Objective Structured Clinical Examination for evaluation of clinical skills of midwifery undergraduate students. Methods: Seven clinical skills were evaluated in this descriptive correlative study using a performance checklist. Census method was used for sampling. Thirty-two midwifery students performed the skills at seven stations each monitored by an observer using an evaluation checklist. Criterion validity was obtained through determining the correlation between the clinical and theoretical courses point and the Objective Structured Clinical Evaluation score. The collected data was analyzed in SPSS (v.20) and logistic regression test. Results: The correlation score of Objective Structured Clinical Examination was significantly related to the mean score of clinical course "Normal and Abnormal delivery I" (0.399, p = 0.024) and the mean score of clinical course "gynaecology "(0.419, p = 0.017). There was no significant correlation between OSCE scores and the mean score of theoretical courses (0.23, p = 0. 200). The correlation between the total score and mean score of students at the stations showed that out of the seven stations, the correlations of the stations three (communication and collecting medical history) and four (childbirth) were not significant. Conclusion: Although, it appeared that Objective Structured Clinical Examination was one of the effective and efficient ways to evaluate clinical competencies and practical skills of students, the tool could not evaluate all the aspects.