To identify the relationship between the competitive intensity of the market and CS rates to help understanding the affecting factors on CS rates in hospitals. The data was extracted from delivery claims which were submitted to Health Insurance Review qqqamp; Assessment Service by hospitals. A total of 419,547 mothers who delivered at 1,077 hospitals in 2006 were selected. Statistical regression techniques were used to identify the associations between intensity of competition and CS rates. The competitive intensity of general hospitals (HHI: 3,901) showed lower than medium-small hospitals (HHI: 4,255). In case of pooling model, the higher the competitive intensity of hospitals in the Korean delivery service market is, the higher the CS rate (OR for HHI 0.893, 95%CI 0.808-0.906). This result was identical in separate model. The competitive intensity between hospitals is determined to be one of the important nonclinical factors that affect the CS rates of healthcare hospitals.