This study investigate the relation between fish consumption, all-cause mortality, and incidence of coronary heart disease (CHD). A total of 4,513 men and 3,984 women aged 30-70 years, sampled randomly from the population in Copenhagen County, Denmark, with initially examination in 1982-1992 was followed until 2000 for all-cause mortality and until 1997 for first admission to hospital or death from CHD. Information on fish consumption was obtained from a self-administered food-frequency questionnaire. Cox proportional hazard analysis gave no evidence for an inverse association between fish consumption and all-cause mortality or incident CHD after adjustment for confounders. Among subjects with a priory-defined high risk of CHD there was a nonsignificant inverse relation between fish intake and CHD morbidity (Hazard Ratio 1.28 (0.92-1.80) for a consumption of fish of less than two times per month or less compared with once a week), but there was relatively few cases in this subgroup. These data provides no evidence for a protective effect of fish consumption on all-cause mortality or incident CHD in the population as a whole, but it cannot be excluded that frequent consumption of fish benefits those at high risk for CHD.