A less favorable cardiovascular risk factor profile, but paradoxically lower coronary heart disease mortality and prevalence have been reported for Hispanic men compared to non-Hispanic white men. Since mortality and prevalence data are susceptible to bias, the patterns of coronary heart disease incidence, as well as prevalence and mortality, were investigated in a biethnic Hispanic and non-Hispanic white population of the San Luis Valley in Colorado. Little evidence was found for lower incidence, prevalence, or mortality due to coronary heart disease among Colorado Hispanics without diabetes. The risk of coronary heart disease among diabetic Hispanics appeared, however, to be approximately 50% lower than among non-Hispanic whites, especially in men. Adjustment for selected cardiovascular risk factors (age, gender, diabetes, hypertension, cigarette smoking, body mass index, and high-density lipoprotein cholesterol and triglycerides levels) did not change this ethnic pattern. The plausible explanations of a lower coronary heart disease risk among diabetic Hispanics, compared to non-Hispanic whites, include both biologic mechanisms and artifacts due to deficiencies of mortality classification or differential access to health care. The existing evidence is insufficient to conclude that the risk of coronary heart disease in the general population differs between Hispanics and non-Hispanic whites. The ethnic patterns of coronary heart disease incidence should be investigated further through population-based incidence studies.