Fish intake is associated with improved cardiovascular health, including a lower risk of arrhythmic death, atrial fibrillation, and heart failure. However, the physiologic effects that may produce these cardiovascular benefits are not well-established. We investigated the cross-sectional associations between a usual dietary intake of fish during the previous year and cardiac structure, function, and hemodynamics as determined by physical examination and 2-dimensional, Doppler, and M-mode transthoracic echocardiography among 5,073 older adults enrolled in the Cardiovascular Health Study. On multivariate-adjusted analyses, consumption of tuna or other broiled or baked fish was associated with a lower heart rate (p < 0.001), lower systemic vascular resistance (p = 0.002), and greater stroke volume (p < 0.001). Tuna/other fish intake was also associated with a higher E/A ratio (p = 0.004), a measure of more normal diastolic function. In contrast, fried fish or fish sandwich (fish burger) intake was associated with left ventricular wall motion abnormalities (p = 0.02), a reduced ejection fraction (p < 0.001), lower cardiac output (p = 0.04), a trend toward a larger left ventricular diastolic dimension (p = 0.07), and higher systemic vascular resistance (p = 0.003). In conclusion, in this large population-based study, the intake of tuna or other broiled or baked fish was associated with improved cardiac hemodynamics, but fried fish intake was associated with structural abnormalities indicative of systolic dysfunction and potential coronary atherosclerosis. These findings suggest potential specific physiologic mechanisms that may, in part, account for the effects of fish intake on cardiovascular health.