Adiponectin (ADP) has been reported to exert cardiac protective effects during ventricular remodeling following pressure overload and myocardial ischemia. However, the potential role of ADP in the volume overload induced heart failure has not been reported. In this study we examined the effect of ADP in cardiac myocyte contractile dysfunction following sustained volume overload. Rat model of volume overload induced heart failure was created by infrarenal aorta-vena cava (A-V) fistula. Some rats were administered with adenoviral ADP (Ad-ADP) at 2-, 6-, and 9-weeks following fistula surgery. Serum total ADP levels were measured at 3 days before, 5 weeks and 10 weeks after fistula surgery. Myocyte contractility and intracellular Ca2+ transients were evaluated at 10 weeks following fistula. Results indicated a progressive reduction of serum ADP levels. In ventricular myocytes isolated from 10-week fistula rats, protein expression of ADP, AdipoR1/R2 and T-cadherin were decreased, and AMPK phosphorylation was reduced. Consistent with these, myocytes exhibited significant depression in cell shortening and intracellular Ca2+ transient. In vivo overexpression of adenovirus-mediated ADP in fistula rats significantly increased ADP serum levels, and prevented the depression of myocyte contractile performance. Moreover, in vitro treatment with ADP significantly improved myocyte contractility and intracellular Ca2+ transient from 10-week fistula rats, but had no effect on myocyte performance in control and Ad-ADP animals. These results demonstrate a positive correlation of ADP reduction and ventricular remodeling induced by volume overload. Adiponectin plays a protective role in volume overload-induced heart failure.