This study used a discrete choice model to investigate an association between air pollution and hospital visits for acute respiratory symptoms with the national health interview survey conducted in 1998 in South Korea. The results showed that NO₂ and TSP were significantly related to hospital visits in a single-pollutant model, but when they were simultaneously considered, only NO₂ remained significant. It was estimated as NO₂ level increased by 10% (0.0027ppm) from 0.027ppm (the mean NO₂ level), hospital visits increase by 0.176%. This study also measured respondent`s out-of-pocket expense and the time cost for commuting and waiting for the visit. We found that on the average, out-of-pocket expense is 5,600 won per hospital visits, but the total cost per hospital visit is measured at 33,440 won with time cost of commuting and waiting at 27,840 won. Time cost was over 63.6∼83.3% of the total cost per hospital visit.