Purpose: This study was tried to identify the effects of simulation practice education on the clinical competence, critical thinking disposition and self-confidence of nursing process in new graduated nurses. Methods: This study was one group pre-post test design, participants are 50 new graduated nurses with less than 3 month of working experience. The simulation practice education applied the first semester of the third grade, over 15 weeks with 1 credit per 2 hours per week by two instructors with four scenarios. Data were analyzed by descriptive statistics, paired t-test, Pearson’s correlation coefficients using the SPSS WIN 21.0 program. Result: There was a significant difference simulation practice education on the clinical competence and critical thinking disposition in the new graduated nurses. There was a correlation between clinical competence and critical thinking disposition. Conclusion: New nurses' capacity can be strengthened by applying simulation practice education that improve the clinical performance by enhance the critical thinking Disposition.