Since the pathology of hypertrophic cardiomyopathy was first described by French pathologists in the mid 19th century, many research papers and extensive reviews for the diverse clinical, pathological and genetics related findings have been published. The common term of hypertrophic cardiomyopathy was suggested to be used by the recommendation of the world health organization in 1980. The characteristic findings have been inappropriate myocardial hypertrophy occurring in the absence of any obvious cause such as aortic stenosis or systemic hypertension, which predominantly involved the interventricular septum in the hyperdynamic and nondilated left ventricle. Hypertrophic cardiomyopathy, initially thought to be rare, is now proved to be an important cause of morbidity and mortality across all ages. It occurs in 1 in 500 live births, and in approximately half of these cases is transmitted as an autosomal dominant trait thus becoming the most common cause of sudden death during exercise in young people. Recently, molecular genetic studies have revealed that it is a heterogeneous disease of the sarcomere in which more than 150 different mutations across 10 sarcomeric proteins are involved, and that the phenotypic manifestation and prognosis varies markedly depending on variations in genetic mutations. Consequently, genetic diagnosis is expected to be available within a few years and able to be used for early diagnosis, prevention and treatment of hypertrophic cardiomyopathy in addition to the currently available morphological and functional diagnosis by two-dimensional and Doppler echocardiography.