This paper examined the effects of private health insurance(PHI) on the health care utilization among the Korean. The used data was the three waves of Korea Health Panel (2008, 2009, 2010), and the number of subjects was 13,951 persons. Authors employed two-stage least square panel model where the instrument variables for controlling for endogeneity of PHI were number of insurance planner per 100,000 in resident area and whether subject worked on financial profession. The results showed that healthcare expenditure of outpatients who purchasing PHI was higher than that of outpatients without PHI, and there was no difference in admission between the two groups. This article recommended the Korean government to monitor the effects of PHI on the health care utilization in order to improve the efficiency of health care finance.