Clinical nursing education is the heart of a nurse's professional practice. Effective and exact clinical evaluation should be the first aim for all nursing faculties and clinical instructors. Objective Structured Clinical Evaluation is one form of objective evaluation method that includes both summative and formative evaluation components. Therefore the application of objective structured clinical evaluation in nursing students' clinical evaluation increase their competencies. Aim of the Study: To compare between objective structured clinical evaluation versus observational checklist in nursing students' clinical evaluation. Methodology: A quasi-experiment design was utilized. A convenience sample of fifty students from third year, Faculty of Nursing, Neelain University, Sudan, Tools; divided into two parts; first part includes Scio-demographic characters and student's clinical evaluation score by both methods and second part included the Student's Opinion regarding advantages of both clinical evaluation methods. Results: Mean of Student's Clinical Evaluation score by Objective Structured Clinical Evaluation was (24.42%), while by Observational Checklist was (20.72). The more than half participant students (66.0%) preferred Objective Structured Clinical Evaluation than traditional observational checklist in clinical evaluation. There was a statistical significance between the Student's Opinion regarding Clinical Evaluation by Objective Structured Clinical Evaluation and Observational checklist in many questions. Conclusion: The findings of the present study concluded that clinical evaluation by Objective Structured Clinical Evaluation more objective method of assessment than the traditional method. Recommendation: Recommendation: Objective Structured Clinical Evaluation should be incorporated with other methods for evaluating undergraduate nursing students in all studying years.