Purpose: This study was designed to investigate the relationships of the types of nurse staffing, the competency of nursing performance and job satisfaction by analyzing the types of nurse staffing in operating room. Method: The subjects were 472 nurses who work in operating room. The instruments used in this study were three tools: competency of nursing performance, job satisfaction and type of nurse staffing. Result: Type 4 was most in the type of nurse staffing of the subjects. According to the type of nurse staffing, the competency of nursing performance was significantly different. There was significant difference in the competency of nursing performance according to age, marital status, bachelor, employ, position, and career, and job satisfaction according to age, position, and career. In opinion about the ideal type of nurse staffing, type 2 was most regardless of career. Conclusion: Type 4 which has lower competency of nursing performance was adopted in many hospitals now but, type 2 which has highest competency of nursing performance was selected by many nurses as the best one. So, it should be considered the type of nurse staffing of in operating room and change it.