Alcoholic hepatitis is an acute life- and health-threatening disease that may be increasingly frequent. However, accurate and representative data on time trends in its incidence and prognosis are not available. This study aims to provide nationwide population-based estimates of alcoholic hepatitis incidence and mortality in Denmark, 1999–2008.We identified, from the Danish National Registry of Patients, all patients with a first-time discharge diagnosis of alcoholic hepatitis from 1999 and through 2008. We also ascertained whether patients had cirrhosis. We computed the annual incidence rates as well as 28-, 84-day, 5-year, and 10-year mortality rates.We found 1951 patients with alcoholic hepatitis, 63% men. During the study decade, the annual incidence rate in the Danish population rose from 37 to 46 per 10 6 for men and from 24 to 34 per 10 6 for women. The steepest increase was observed among middle-aged women. The 28-day mortality rate rose from 12% to 15%, and the 84-day mortality rate rose from 14% to 24%, similarly for men and women. The increase in short-term mortality was attributable to increasing patient age and prevalence of cirrhosis. The 5-year mortality was 56% overall, 47% without cirrhosis, and 69% with cirrhosis.The incidence of alcoholic hepatitis in Denmark has increased during the recent decade. The patients are older at diagnosis and more have cirrhosis, resulting in worse short-term prognosis. The long-term prognosis is grave, especially for patients with cirrhosis. The increase in incidence mirrors changes in alcohol consumption in Denmark.