Male offspring of adult females treated with 0.2 or 0.4 mg/kg during either the whole of pregnancy or the whole of the lactation period did not induce generalised toxic effects. A significant alteration in enzymatic activities i.e. SDH (decreased), LDH and Y-GT (increased) were observed in testes only at 0.4 mg/kg. A decrease in sperm motility, sperm count along with increase in percent abnormal sperm was observed at 0.4 mg/kg dose level. Histopathological examination revealed loss of spermato-genesis, degenerative changes in Sertoli cells which are well supported with biochemical studies indicating that carbofuran interferes with the maturation process of testis. No such effects were observed at 0.2 mg/kg. The testicular and spermatotoxic effects observed in rats given in utero or lactational exposure may be due to transfer of carbofuran or its metabolites through placenta or mothers milk.