Taking purple sweet potato as the experiment material，a pot experiment method was carried to study the characteristics of selenium absorption and accumulation in purple sweet potato.The seleniumenrichment difference of purple sweet potato under selenate \[Se(VI)\] and selenite \[Se(IV)\] treatment was compared.The results showed that both selenate and selenite increased the selenium concentration of the purple sweet potato significantly and the selenium concentrations in plant organs had a positive correlation with the selenium application.The highest selenium content of purple sweet potato in roottuber were 6.69 mg/kg(DW)and 0.88 mg/kg(DW)，respectively，with application of Se 8 mg/kg soil by selenate and selenite.On 40 d of the growth，the selenium concentration order in different organs of purple sweet potato was leaf>stem>roottuber，while the order on the 130 d of the growth was leaf> roottuber>stem.The highest selenium accumulation of purple sweet potato roottuber reached 923.81 μg/plant under 4 mg/kg selenate treatment.The distribution rate of Se in roottuber of purple sweet potato was between 67%~70%，the absorption rate of selenate was significantly higher than that of selenite.Considering selenium enrichment and the growth of purple sweet potato，both selenate and selenite were helpful for seleniumenrichment purple sweet potato production，the sensibility of sweet potato to selenate exceeded that of selenite，and the biological safety for crops should be taken full account of in the production process.