Objectives : The Korean government in January 2006 instigated an exemption policy for hospitalized children under the age of six years old. This study examines how this policy affected the utilization of medical care in Korea. Methods : A total of 1,513,797 claim records from the Health Insurance Review Agency were analyzed by complete enumeration methods. The changes of medical utilization were compared from 2005 to 2006. In addition, the changes of medical utilization between 2004 and 2005 were compared as a pseudo-control group. Results : The admission rate increased 1.14-fold from 15.20% in 2004 to 17.32% in 2005, and this further increased 1.08-fold to 18.65% in 2006. The increase of patients with a common cold (1.2-fold) was higher than that of both the general patients (1.08-fold) and the patients, with the top 10 fatal diseases (0.91-fold). The average length of stay per case for clinics showed the highest increase rates (1.06-fold). The rates of patients with the common cold showed a higher increase (1.05-fold) than that of the general patients. The average medical expense per case was increased by 1.10-fold from 2005 to 2006, which was higher than that from 2004 to 2005 (1.04-fold). The increase rate for patients with the common cold was higher at 1.18-fold than that of the general patients. Conclusions : The cost exemption policy has especially led to an increase in the utilization of clinics and the utilization by patients with a common cold.