OBJECT: To investigate the characteristics of diffuse idiopathic hyperostosis (DISH) in Koreans. METHODS: The nine patients of DISH were investigated in terms of symptom, involved area in simple X-ray, accompaning disease, serum uric acid level, and serum triglyceride and cholesterol. RESULTS: Eight of nine patients were male, one patient was female, and their mean age was 64. Their symptoms were no symptom(2/9), neck pain(2/9), dorsal pain(2/9), and low back pain(3/9). The involved areas were the cervical vertebrae(1/9), the lower thoracic vertebrae(3/9), or the lower thoracic and upper lumbar vertebrae(5/9). The accompaning diseases were ankylosing spondylitis (1/9), degenerat,ive joint disease (2/9), posterior laminectomy (1/9), diabetes mellitus (1/9), chronic active hepatitis (1/9), cerebrovascular accident (2/9), hypertension(2/9), chronic renal failure(2/9), and gout(2/9). In the cases involving thoracic vertebrae, the ossification was seen dominantly in the right side. Four of nine patients had diabetes mellitus, hyperuricemia (7. 0 mg/dl in male and 6.6 mg/dl in female), or dyslipidemia (194 mg/dl in serum triglycerid level and 275 mg/dl in serum cholesterol level). CONCLUSIONS: In our cases of DISH, it was dominant in male and old age, and the diabetes mellitus or hyperuricemia was more frequently found than in general population.