The proportion of cancer as a cause of death in Korean has been continuously increasing. In 2000, 24 %(59,020 of 247,346) of deaths were caused by cancer. Occupational exposure would have contributed to the development of some cancers. It would have accounted for more than 2,000 cancers in a year if 4% of all cancer or 10% of lung cancer was regarded as arising from the work environment. However, occupational cancer has not been reported as much as expected. The first case of occupational cancer reported officially was mesothelioma caused by asbestos exposure at an asbestos textile industry in 1992. Following the report, many cases of occupational cancers have been reported such as lung cancer due to exposure to asbestos, chromium, exhaust gases, coke oven emissions, and silica, as well as leukemia due to exposure to benzene or other solvent and bladder cancer arising from exposure to benzidine salts. The Health Examination for retirees has been conducted since 1992 in order to detect occupational cancer early in workers who have been exposed to 11 carcinogenic substances. However, to date no occupational cancer has been detected through the Retirees' Health Examination. The Korea Labor Welfare Corporation(KLWC) has referred 108 claims for occupational cancer to the Korea Occupational Safety and Health Agency(KOSHA) between 1992 and 2000. Thirty-three cases were accepted, including 14 cases of lung cancer, eight cases of hematopoietic cancer and six cases of mesothelioma. KLWC has accepted the claim for primary lung cancer developed with pneumoconiosis as an occupational cancer, of which there were 31 cases in 1999 and 61 cases in 2000. In conclusion, special attention is required to detect occupational cancer due to their long latency period and the fact they are usually found after retirement.