Abstract: The aim of the present study was investigation of antitoxin effects of green tea on malathion toxicity in rats. Forty eight rats were divided into 4 groups, control, extract green tea (1% w/v, daily), malathion (135 mg kg-1 i.p., daily) and rats injected with malathion and treated with crude green tea. After 5 weeks, the animals were weighed and autopsied for detailed histopathological and haematological studies on the last day after final dosing. Insignificant changes in blood hemoglobin was shown when compared to control except increase in WBC count (p≤0.05) and significant decrease in RBC count (p≤0.05). Histopathological findings of lung tissue samples were significantly different in comparison of controls and the experimental rats, where the normal alveolar structure in group 1, 2 and 4, but increased alveolar macrophages and interstitial neutrophil infiltration and minimal fibrosis were detected in malathion group. The repair and recover of lung tissue injuries occur in group 4 may due to the antioxidant, antitoxin and chemopretective properties of different components of green tea. So, the present study recommends that the using crude green tea or active biological components in prevention the toxicity of pesticides such as malathion.