This study was performed to investigate the distribution of indoor air pollutants in medical facility in Gyeonggi-do area from February to November, 2012, and to conduct the health risk assessment from obtained data. PM10, CO₂, formaldehyde, CO, and total bacteria count(TBC) did not exceed the maintained standards, but mean concentration of TVOC was 402.3 ㎍/㎥ and thirteen of them exceeded the recommended standard. In the concentration distribution of pollutants for the monthly samples, CO₂, formaldehyde, TVOC, TBC were the highest level in August. From the factor analysis of indoor air pollution provided three factors; the first factor was seasonal factor (indoor temperature and humidity, TBC and formaldehyde), the second factor was ventilation factor (CO₂, PM10 and CO), and the third factor was building(or interior) factor (TVOCs). In the health risk assessment results, the excess carcinogenesis of formaldehyde for resonable maximum exposure worker was 1.21×10-⁴ which means exceeding the cancer criteria(1.0×10-⁴). We confirmed the probability of health effect caused by TVOC. The lifetime excess cancer risk of carcinogens(benzene, formaldehyde) and hazard quotient of non-carcinogens(toluene, ethylbenzene, xylene, styrene), and risk of regulation substances(PM10, CO₂) were safety level for inpatients and out patients.