This study was carried out to assess the reproductive toxicity of 2-bromopropane (S-BP) using spermatogenesis stage classification and Sertoli cell indices (SCI).Vehicle control olive oil and 2-BP doses of 125, 250 and 500 mg/kg of body weight were injected in the interaperitoneum of 12 weeks male Sprague-Dawley rats for 28 days respectively of SCI on germ cells including the spermatogonia of stages II-III, Ⅵ,Ⅹ, XII, ⅩIII, and spermatocytes of stages VIII (preleptotene), Ⅹ (leptotene), XII (leptotene), V and Ⅵ (pachytene), and the round spermatids of stage Ⅵ. Considering the process of maturation depletion in spermatonesis, spermatogonia may be the primary target cells of 2-BP toxicity.