Abstract: In order to explore the possible mechanisms of organophosphorus insecticide in pig, healthy Xiang pigs were divided randomly into three groups, dichlorvos, high fat diet and control group. After 12 months feeding, we analyzed the changes of pathology and related enzyme activity in liver, kidney and artery, respectively. The subtoxic dosage of dichlorvos was determined to be 2.5 mg·(kg·2d)-1 by preliminary experiments. The results showed that dichlorvos damaged the liver and kidney cells of Xiang pig, and decreased activities of cholinesterase (ChE) and paraoxonase1 (PON1) significantly (P＜0.01), whereas there is no significantly effect on the artery, serum lipid levels and body weight. In the high fat diet group, the body weight, the level of ChE, total cholesterol (TC), low density lipoprotein (LDL) and high density lipoprotein (HDL) were increased obviously (P＜0.05) than control, while the activity of PON1 and its mRNA level were decreased (P＜0.05). Furthermore, atherosclerosis lesion (AS) in carotid was observed, but the lesion in liver and kidney in the high fat diet group was not as seriously as that in the dichlorvos group. It illustrated that both of dichlorvos at subtoxic dosage and high fat diets could stimulate the oxidative stress reaction and inhibit the PON1 activity by different pathway. Therefore, it should be pay more attention on the organophosphorus pollution to prevent the lesion in pig individuals.