Background The future burden of heart failure in Japan was projected to 2055 in order to prospectively estimate of the number of these patients. Methods and Results The statistics are based on prevalence data of left ventricular dysfunction (LVD) in Sado City using the Sado Heart Failure Study (2003) and population estimates from the Japanese National Institute of Population and Social Security Research Report (2006). The number of Japanese outpatients with LVD was 979,000 in 2005, and is predicted to increase gradually as the population ages, reaching 1.3 million by 2030. Conclusion LVD is expected to precipitate a future epidemic of heart failure in Japan. (Circ J 2008; 72: 489 - 491)