Objective To explore the antagonism effects of different doses of zinc on testicular toxicity induced by arsenic. Methods Fifty male Sprague-Dawley rats were randomly divided into five groups: control group, arsenic group (4 mg/kg NaAsO2), arsenic plus low-dose zinc group (4 mg/kg NaAsO2+8 mg/kg ZnSO4), arsenic plus mid-dose zinc group (4 mg/kg NaAsO2+20 mg/kg ZnSO4), and arsenic plus high-dose zinc group (4 mg/kg NaAsO2+50 mg/kg ZnSO4). Intragastric administration was applied for 60 consecutive days. The testes were observed with hematoxylin-eosin (HE) staining. The expression of Fas protein was examined by immunohistochemistry staining. The concentration of testosterone in serum was examined by radioimmunoassay. The zinc content in testis was determined by atomic absorbing spectrometry. The levels of malondialdehyde (MDA), lactic dehydrogenase (LDH), and superoxide dismutase (SOD) were measured by enzymelinked immunosorbent assay (ELISA). Results Compared to control group, arsenic administration caused remarkable decreases of spermatogenic cells and vacuolization of seminiferous tubular cells, and higher expression of Fas, significant reduction of zinc content, lower testosterone concentration, and significantly aggravated lipid peroxidation were observed in arsenic group (P<0.05). Compared to arsenic group, zinc treatment significantly reduced the expression of Fas, increased serum testosterone level, and alleviated lipid peroxidation (P<0.05). The protective effect of mid-dose zinc was the best. There were no differences in the levels of MDA and LDH between arsenic group and arsenic plus low-dose zinc group. Conclusion Arsenic can lead to testis damage which may cause reproductive functional impairment. Zinc treatment can antagonize the toxicity of arsenic when the dosage of zinc is suitable.