Objectives : Both organized and opportunistic screening programs have been widely used in Korea. This paper examined the determinants of the use of opportunistic screening programs in Korea. Methods : The subjects were a national stratified random sample of 10,254 people aged 45 or older from the first wave of the Korean Longitudinal Study of Ageing in 2006. A logit model was used to examine the determinants of the use of opportunistic screening programs in terms of the demographic and socioeconomic characteristics, the type of health insurance and the health status. Results : Thirteen point seven percent of the individuals received opportunistic screening programs within 2 years from the time the survey was conducted in 2006. The individuals who graduated from college or who had even more education were 3.0 times more likely to use opportunistic screening programs compared with the individuals who were illiterate. The individuals who resided in urban areas and who had religious beliefs were more likely to receive opportunistic screening programs compared with their counterparts. Those who were in the first quartile for the total household assets were 2.6 times more likely to use opportunistic screening programs than those who were in the fourth quartile for the total household assets. Privately insured people were 1.6 times more likely to use opportunistic screening programs than those who were not insured. Finally, the individuals who self-assessed their health status as worst were 2.1 times more likely to use opportunistic screening programs compared individuals who self-assessed their health status as best. Conclusions : This study suggests that opportunistic screening programs can be an indicator for whether or not an individual is among the advantaged group in terms of their socioeconomic characteristics and type of health insurance.