Purpose: The purpose of this study was to identify the effect of a simulation-based practice on clinical performance and problem solving processes for nursing students. Method: The study used a one group pre-post test design. Students experienced a simulation-based practice that included team base learning, skill training, taking a high-fidelity simulation with SimMan 3G, and also being debriefed for 12 weeks (August 2010 to December 2010). The pre-test and post-test were conducted to compare the differences in knowledge, clinical nursing skills, and problem solving processes. Result: After students had received the simulation-based practice, they showed statistically significant higher knowledge (t=14.73, p<.001) and clinical nursing skills (t=15.47, p<.001) than before. However, there was no significant difference in the problem solving process score (t=1.53, p=.127). Conclusion: This study showed that knowledge and clinical nursing skills were significantly improved by the simulation-based practice. Further research would be required to identify how the problem solving process that uses simulation-based practice could be developed further.