Objective:To evaluate the dose and duration dependent cytotoxicity of aroclor 1254 on mice testis.Methods: The study tests the hypothesis that in vivo exposure of very low dose aroclor 1254, comparable to that of possible human exposure from different environmental sources, will provoke dose and duration dependent histological damage in the mice testis. Male mice were orally administered with the two doses 0.1 and 1 mg/kg b.w /d. of aroclor 1254 for 7, 14, 21 and 28 days.Results:Results showed the degenerative changes in the testis of mice, namely, atrophied seminiferous tubules, expanded space in interstitial and necrosis in the germinal epithelial cells of seminiferous tubules, of the seminiferous tubules and deceleration of spermatogenesis.Conclusions: Therefore, the results of the present study suggested that the sub-acute exposure of very low doses of aroclor 1254, can subsequently mediate the cytoskeleton dysfunction in the testis of mice.