This work was designed to investigate the toxicity of arsenic caused by oral exposure to rice-simulated arsenic species in four dose groups (C, S: 0.91 mg/kg, M: 9.1 mg/kg and H: 30 mg/kg) and its biotransformation. The arsenic content and arsenic species (iAsⅢ, iAsⅤ, MMAⅤ, DMAⅤ and AsB) distribution in the bowel, blood, liver and kidney of mice were determined by ICP-MS and HPLC-ICP-MS, respectively. The histological changes of bowel tissue, liver and kidney were observed by light microscope after H&E staining. The results showed that in the group of C, S, M and H, the total arsenic concentrations in the blood were 5.33, 8.24, 55.75 and 196.49 μg/kg, respectively; and in the liver were 14.34, 32.70, 237.10 and 708.74 μg/kg, respectively; The sum of the five arsenic species concentrations in the bowel were 27.97, 163.12, 892.78 and 3085.325 μg/kg, respectively; and in the kidney were 10.38, 25.79, 245.85, and 1654.14 μg/kg, respectively. The dominant arsenic species in the bowel were iAsⅢ and DMA. The ratio of organic arsenic to inorganic arsenic in the blood increased with the exposure dose. The main arsenic species in the liver and kidney is DMA. Compared with the control group, the degree of pathological damage in the bowel, liver and kidney of test group was deepened with the increase of arsenic exposure dose. This study shows that the short-term arsenic exposure in rice has no obvious damage to the metabolic tissues of the body, and the accumulation of arsenic in the tissues is less; the high-dose arsenic exposure in rice will cause serious damage to the pathological structure of the body; it suggests that the long-term low-dose arsenic exposure in rice might also cause damage to the body.