The National Clinical Database of Japan( NCD) was established in April 2010 in the collaboration of 9 surgical subspecialty societies on the platform of the Japan Surgical Society(JSS). Registrations began in 2011, and because NCD is strongly linked to the board certification system by JSS, the ratio of registration of surgical procedures is very high, over than 97%. To date, more than 4,000 facilities have enrolled and over 7 million cases were registered over a 5-year period. The analyses of NCD are compared to the foreign database, such as American College of Surgeon National Surgical Quality Improvement Program in the gastrointestinal (GI) surgical field, and the Society of Thoracic Surgeons National Adult Cardiac Database in the cardiovascular surgical field, with a goal of creating a standardized surgery database for quality improvement. Also, from 2014, NCD has started to send feedback reports of mortality and morbidity to participants in the 8 GI procedures, namely esophagectomy, gastrectomy, hepatectomy and so on. Furthermore, NCD supports many clinical researches for providing high-quality healthcare to patients and the general public. NCD's activities are conducted lawfully and ethically with due consideration of its effects on society. NCD will continue to ensure the reliability of collected data, to guarantee the scientific analysis, and to discuss the future evolution.