Cardiac hypertrophy is a commonly observed complication of a variety of cardiovascular diseases. As well as mechanical stresses such as pressure overload, several humoral factors may contribute to the development of cardiac hypertrophy. In the early 1990s, endothelin-1 (ET-1) was found to induce cardiomyocyte hypertrophy in cultured neonatal rat cardiomyocytes. Furthermore, evidence is accumulating to date to support the postulate that ET-1 may function as an autocrine/paracrine factor in the development of cardiac hypertrophy in vivo as well as in vitro In this review article, I discuss physiological and pathophysiological roles of ET-1 and its related peptides in cardiac hypertrophy associated with various cardiovascular diseases.