Cancer is the leading cause of death and one of the most significant healthcare expenses in Korea. The purpose of this study was to estimate the economic burden of cancer on Korean society. We studied the medical, non-medical, morbidity and mortality costs related to cancer treatment, lost productivity and premature death. Healthcare claims for 2002 obtained from the Health Insurance Review Agency were used to estimate medical expenditures; these were linked with the Korean Central Cancer Registry database to identify cancer patients. The number of deaths used to estimate mortality costs was obtained from the Annual Report of Mortality from the National Statistics Office of Korea. Moreover, data from the Korean National Statistics Office and Ministry of Labor were used to calculate life expectancy at the age of death, labour force participation, and average age- and gender-specific earnings. In 2002, the estimated total economic cost of cancer amounted to $9.4 billion (1.72% of GDP) at a 3% discount rate. Medical care costs amounted to 13.7% of total costs, non-medical costs 6.5%, morbidity costs 14.5%, and mortality costs accounted for 65.3%. Increased prevention, earlier diagnosis, new therapies and effective cancer control policies are needed to reduce the economic burden of cancer in Korea.