The objective of the present study was to determine the association between plasma adiponectin and left ventricular (LV) systolic function. Baseline plasma adiponectin was measured in 389 patients undergoing coronary angiography for a variety of indications at a Veterans Affairs Medical Center. Detailed demographic, clinical, laboratory, and angiographic data were available for patients. LV systolic function was assessed using ventriculography, and patients were grouped into those with normal or mild dysfunction (ejection fraction ≥45%) versus those with moderate to severe systolic dysfunction (ejection fraction <45%). After adjusting for a variety of clinically relevant covariates known to affect LV systolic function, adiponectin was independently associated with LV systolic function in the entire cohort of patients (p = 0.0002) using multivariate linear regression analysis. In addition, using multivariate logistic regression analysis, adiponectin was an independent predictor of the presence of moderate to severe LV dysfunction (odds ratio 1.54, 95% confidence interval 1.21 to 1.97, p = 0.0005). Moreover, baseline adiponectin was also independently associated with LV function in both the myocardial infarction (MI) and non-MI subpopulations of patients (p = 0.0401 and p= 0.0023, respectively). Finally, in the non-MI subpopulation, baseline adiponectin was an independent predictor of moderate to severe LV systolic dysfunction (odds ratio 1.52, 95% confidence interval 1.15 to 2.02, p = 0.0034). In conclusion, baseline plasma adiponectin was an independent predictor of LV systolic dysfunction in a population of patients referred for coronary angiography.