Fish consumption has been associated with a lower risk of coronary heart disease (CHD) in some but not all studies. We conducted a meta-analysis of observational studies to determine if fish consumption is associated with lower fatal and total CHD. English language articles published before May 2003 were searched. In all, 19 observational studies (14 cohort and 5 case-control) in which there was a group that consumed fish on a regular basis and a comparison group that consumed little or no fish were included. With use of a standardized protocol and data extraction form, information on study design, sample size, participant characteristics, duration of follow-up, assessment of end points, and consumption of fish was abstracted. Using a random effects model, we pooled data from each study. Fish consumption versus little to no fish consumption was associated with a relative risk of 0.83 (95% confidence interval 0.76 to 0.90; p <0.005) for fatal CHD and a relative risk of 0.86 (95% confidence interval 0.81 to 0.92; p <0.005) for total CHD. The results indicate that fish consumption is associated with a significantly lower risk of fatal and total CHD. These findings suggest that fish consumption may be an important component of lifestyle modification for the prevention of CHD.