OBJECTIVE: Arrhythmogenic right ventricular cardiomyopathy(ARVC) is a progressive cardiac muscle disease characterized as progressive fibrofatty replacement of the right ventricle, severe ventricular arrhythmia, and sudden death. However, there is no report of ARVC as a cause of sudden death in Korea. METHODS and RESULTS: Postmortem studies were done to 115 cases of sudden unexplained death at department of legal medicine, school of medicine, Kyungpook national university in year 1999. We identified 7 cases(6%) of typical ARVC with no other identifiable cause of sudden death. The subjects included 5 males and 2 females, ranging in age from 19 to 41 years (mean 29.7 years). All were found dead at bed (5 cases) or workshop (2 cases). Five cases were fibrofatty types and two cases were fatty types. Right ventricular aneurysm, inflammatory infiltrates and left ventricular involvement were found in 4, 2 and 1 cases, repectively. Two cases had family history of sudden death before age 40. No one was suspected of having cardiovascular disease or ARVC before death. CONCLUSION: These findings indicate that ARVC in Taegu-Kyungpook area may be more frequent than previously thought. ARVC may be a major cause of sudden unexplained death.