Abstract: Objective:The effects of dietary intake with the Antarctic krill oil and its arsenobetaine(AsB)on the arsenic speciation composition in the rat viscera were studied using a new established high performance liquid chromatography-atomic fluorescence spectrometry(HPLC-AFS)method. Methods:Male Wistar rats were randomly divided into six groups(5 each):soybean oil control groups(7,30 d),krill oil groups(7,30 d),krill oil added 100 mg/kg arsenobetaine groups(7,30 d). After 7 and 30 d of feeding at the same dose of 2.625 g/kg·bw,the rats were sacrificed and the livers and kidneys were excised. The contents of AsB,dimethyl arsenic acid(DMA),methyl arsenic acid(MMA),arsenite(AsⅢ)and arsenate(AsⅤ)in the viscera were analyzed by the established HPLC-AFS method. The separation column was Hamilton PRPx-100,while the mobile phase was ammonium dihydrogen phosphate buffer. Results:Under the established analysis conditions,the LOD of the five arsenic compounds in the rat viscera was 0.35~0.50 μg/L and the LOQ was 1.0~2.0 μg/L. The spike recoveries of the five arsenic compounds at three fortified concentrations ranged from 80.2% to 113.0%. The RSD was 1.34% to 3.97%,the method showed a good linear relationship,R²>0.999. The main arsenic speciation in the rat livers and kidneys were AsB and DMA. After 7 and 30 d of feeding with the krill oil and its AsB,the contents of total arsenic,AsB,AsⅢ,DMA,MMA and AsⅤin the viscera showed no significant differences compared to the control groups. Conclusion:No arsenic accumulation effects in the rat viscera would appear after dietary intake with the krill oil. Furthermore,the krill oil and its AsB had no significant effects on the changes of the arsenic speciation contents and the transformation between the different arsenic compounds in the rat viscera. This research provided theoretical supports for the scientific recognition of the edible safety of the krill oil as well as the expansion of its application fields.