Objective To assess the feasibility,acceptability and effects of mini-clinical evaluation exercise(mini-CEX)for performance evaluation among students or graduate students of oral and maxillofacial surgery outpatient or emergency department.Methods From 2010 to 2011,the clinical performances of forty medical college students in the outpatient department of oral and maxillofacial surgery or department of oral emergency were evaluated by three doctors.Four to eight times assessments were performed for every student during the entire study period.The patients were elected randomly in the outpatient or emergency department of oral and maxillofacial surgery,who were informed and consent to the study.Every participant assessed the evaluation at the end of the evaluation.We analyzed the processes and results of the evaluation,and assessed the effects of mini-CEX in the performance evaluation among students or graduate students of oral and maxillofacial surgery outpatient or emergency department.Results We completed 265 successfully evaluations.It took 25.3 minutes for the evaluation,and 4.1 minutes for the feedback in mean.At the end of teaching course,all students met the teaching requirement.All participants were satisfied with this kind of mini-CEX,and all participants believed that mini-CEX was a good evaluation and learning tool,too.Conclusions The mini-CEX is a reliable tool for learning and performance evaluation of students or graduate students of oral and maxillofacial surgery outpatient or emergency department,and is acceptable and well received by both students and supervisors.