Individuals with a family history of coronary heart disease (CHD) may be predisposed to atherothrombosis. To investigate this hypothesis, a family CHD risk score was computed for approximately 13,000 men and women aged 45 to 64; hemostatic variables (fibrinogen, factor VIIc, factor VIIIC, von Willebrand factor, antithrombin III, protein C) were also measured in plasma. After adjustment for age and ethnicity, there was a statistically significant, positive association between the family risk score and four of the six hemostatic variables (fibrinogen, factor VIIc, factor VIIIc, von Willebrand factor) in women and all six hemostatic variables in men. In general, these associations were weak and substantially attenuated after adjustment for constitutional, lifestyle, and biochemical covariates. These results indicate that mean levels of selected hemostatic variables, like traditional CHD risk factors, are higher in individuals with a family history of heart disease.