Purpose: This study was conducted to examine the effects of simulation-based education on communication skill and clinical competence in maternity nursing practicum. Methods: This study used a non-equivalent control pretest-posttest design. The simulation-based education in maternity nursing practicum consisted of two clinical situation scenarios pertaining to patients with normal and high-risk deliveries. The control group consisted of 35 students in 2010 and the experimental group consisted of 35 students in 2009. The experimental group was given the simulation-based education using a high-fidelity patient simulator over 3 sessions, whereas the control group was given a conventional pre-clinical practice orientation before maternity nursing clinical practicum. Data were collected using a questionnaire, which included questions to assess communication skill and clinical competence. Data were analyzed using SPSS/WIN 18.0. Results: Members of the experimental group, who received the simulation-based education, showed significantly higher communication skill and clinical competence scores than the control group (t=-2.39, p = .020; t=-2.71, p = .009). Conclusion: The simulation-based education in maternity nursing practicum is effective in promoting communication skill and clinical competence. With application of diverse clinical situation scenarios, it is recommended to develop and apply simulation-based education using a high-fidelity simulator in the area of maternity nursing.