Ethylenediamine dihydrochloride (EDA X 2 HCl) was incorporated in the diet of Fischer 344 rats at dosage goals of 0.50, 0.15, 0.05, or 0 g/kg/day in a two-generation reproduction study. The parent generation (F0) and the F1 generation were each bred once. Parameters examined included indices of fertility, gestation of dams, gestation survival, 0- to 4-, 4- to 14- and 4- to 21-day survival of pups, number of pups born alive, and number of pups weaned per litter. Furthermore, observations were made on mortality, diet consumption, and body weight of the adult rats in F0 and F1 generation. Randomly selected F1 weanlings and adults and F2 weanlings were sacrificed and organ weights were obtained; in addition, gross and histologic examinations were conducted on these rats. No reproductive toxicity was observed in this study. Some effects were observed in both sexes for the F0 and F1 parent rats. These effects were mainly associated with the high dosage level and included reduction of body weight gain and changes in liver (decrease) and kidney (increase) weights in the adult rats. The only microscopic lesion observed was hepatocellular pleomorphism in the high level F1 adult males and females; a greater prevalence and severity of this lesion was seen in the female rats.