OBJECTIVES: The purpose of this study was to analyze the characteristics of workrelated musculoskeletal diseases, as listed by the Korea Labor Welfare Corporation (KLWC). METHODS: Using the database of the KLWC, we collected information from 410 approved occupational musculoskeletal disease cases, which occurred between 1 January and 31 December 1999 and were approved by 30 June in 2000. We investigated the characteristics of the disease using a mail survey and telephone interviews. The characteristics we investigated included : sex, age, disease-related working duration, process of disease occurrence, type of enterprises, etc. RESULTS: Men accounted for 75.6 % (310 workers) of the approved cases. The most common age group was 30-39 years (n=143, 34.9 %). The mean disease-related working duration was 5.7 years, and the most commonly had a work-duration of 1-5 years (n=108, 36.0 %). The major industrial types of enterprise were manufacturing (235 workers, 57.3 %), transportation (46 workers, 11.2 %), and construction (25 workers, 6.1 %). Within the manufacturing industry, the most common was motor vehicles and trailers manufacturing. Within the group, the most common jobs were plant or machine operators and assemblers (129 workers, 36.5 %), elementary occupations (90 workers, 25.5 %), and craft and related trades workers (63 workers, 17.8 %). The majority of the diseases involved lumbar problems (232 cases, 54.7 %), neck and upper extremity diseases (183 cases, 43.2 %) and lower extremity diseases (9 cases, 2.1 %). In the cases of lumbar disease, the mean age and working duration was 36.5 years and 4.7 years, respectively. Fifty-four cases of lumbar diseases were due to repetitive work and 89 due to non-repetitive work. Bad posture at work was the most common cause for those doing repetitive work(23 cases), and lifting the most common cause of problems in the non-repetitive work cases (27). CONCLUSIONS: We were able to elucidate the characteristics of workers with approved occupational musculoskeletal disease through this study. Many approved cases occurred in women, and workers performing repetitive work, of these herniated nucleus pulposus occurred in many workers performing simple repetitive works without serious external forces. This suggests that a prevention policy for occupational musculoskeletal disease must be established, to focusing on the above-mentioned high-risk groups.