The purpose of the study was to establish a competency-based clinical performance examination model in maternity nursing for baccalaureate students. Action research was the main research methodology used in the study. A committee, consisting of nursing faculty, students and experienced obstetric nurses, was established to develop the model. Based on intensive literature reviews and standards of nursing practice in Taiwan, the first draft of the model, including the content and process, was created by the committee. The draft then was revised twice after expert review and pilot testing. The revised version of the model was formally implemented into the curriculum to examine the competencies of forty-one BSN students at the end of the perinatal nursing course. Responses from students, clinical examiners, clinical staff and clients were all gathered and integrated to refine the model. The model has content, expert and discriminative validity. The reliability of the model was proven by the high consistency in administration and scoring of the model among clinical examiners.