Several studies were undertaken to determine the effect of dehydroepiandrosterone (DHEA) on growth in Zucker rats. In experiment 1, 3 weeks of DHEA treatment in lean rats resulted in decreased body weight gain in comparison to control rats. In experiment 2, both lean and obese rats were treated with DHEA from 6 to 21 weeks of age. Significant decreases in body weight were found for both lean and obsese DHEA-treated rats. The food efficiency ratio (FER) was significantly decreased in both DHEA-treated groups. Significant decreases in parametrial and retroperitoneal fat pads were found in both lean and obese DHEA-treated rats. This was primarily attributed to a decrease in fat cell number in lean rats and to decreases in both number and size of fat cells in obese rats. In experiment 3 obese female rats were treated with DHEA from 6 to 21 weeks of age followed by 15 weeks with DHEA removed from the diet. Significantly more weight was gained by the rats previously treated than by the control rats, but body weight remained significantly lower than in the control groups. These data indicate DHEA has an effect on altering body weight and body fat in lean and obese Zucker rats.