Abstract: [Objective] This project aims to make clear the biotype distribution of Bemisia tabaci in the main agricultural areas of Xinjiang and commonly used pesticides resistance level in order to provide a scientific basis for scientific prevention and pesticides resistance management.[Method]Mitochondrial cytochrome oxidase I gene(mtCOI)enzyme sequence amplification polymorphism(CAPs)technology was applied to identify the whiteflies biotype.The resistances to 11 commonly used insecticides in Yining,Hotan,Shache,Turpan and Changji were determined by the methods of leaf-dipping and egg impregnation leaf-dipping.[Result]Biological identification showed that Q type was distributed in the 5 tested field populations.Bemisia tabaci in Hotan was a mixed type with B dominant species.Those found in Yining,Shache,Changji and Turpan belonged to type Q.Resistance monitoring showed that the high level of resistance to imidacloprid resistant population in Turpan reached 57.67 times.The population of Yining was only resistant to Imidacloprid.Those populations in Turpan,Shache,Hotan and Changji resulted in from low to high levels of resistance to imidacloprid,thiamethoxam,acetamiprid and dinotefuran(RR was 5.53-57.67 times)and led to from low to middle levels of resistance to pymetrozine+isoprocarb(RR 5.14-31.92 times);Populations in Turpan and Changji displayed moderate level resistance to avermectins and cyantraniliprole(RR 31.67-32.73 times,10.93-29.57 times)and to low to moderate level resistance to sulfoxaflor(RR 9.7-11.66 times).Shache,Yining and Turpan populations exhibited low to moderate level resistance to pyriproxyfen(RR7.96-31.33 times).[Conclusion]The tested five Bemisia tabaci field populations' biotypes mainly belong to Q biotype with a small amount of B biotype.Different Bemisia tabaci biotype shows different resistance levels,among which,the highest level of resistance is to the Imidacloprid.Resistance management should be carried out according to the local resistance level to pesticides.