Serum cholesterol has been increasing in recent years in Japan. There is concern that risk of coronary heart disease (CHD) may be increasing too, but there is little information on validated fatal CHD trends in the Japanese population. We identified 1,056 deaths from heart disease and other deaths possibly hiding CHD from death certificates of residents aged 25-74 years in Oita City, Japan in 1987-1988, 1992-1993, and 1997-1998 (mean population, 273,000 in 1997-1998). We validated 994 of them by medical record review and physician interviews, classifying them into definite fatal acute myocardial infarction (AMI) and possible fatal AMI or CHD death based on Monitoring Trends and Determinants in Cardiovascular Disease project's criteria. Sudden death was defined to estimate the number of CHD sudden deaths. In men, age-adjusted mortality rates due to validated fatal CHD remained quite stable over 10 years (25.3 per 100,000 [95% CI, 15.0-35.5] in 1987-1988 to 24.2 per 100,000 [95% CI, 16.1-32.3] in 1997-1998). When 50% or all sudden deaths were included as fatal CHD, the rates for men tended to decline. This was due to decreasing out-of-hospital deaths in connection with a declining CHD death rate among men aged 65-74 years, whereas in-hospital CHD deaths were level. In women, the rate of validated fatal CHD was highest in 1992-1993, but the 1997-1998 rate was similar to the 1987-1988 rate. We did not find that fatal CHD rates increased in Oita men and women from 1987-1998. Rather, out-of-hospital fatal CHD tended to decline in Oita men.