Abstract:The effects of two type cottons, Bt-cotton Guokang 22 (GK22) and non-Bt cotton Simian 3 (S3), on the development and reproduction of sweet potato whitefly, Bemisia tabaci (Gennadius), were investigated both under lab constant temperature and field inconstant temperature conditions. The results indicated that the developmental time (from egg to adult) of B. tabaci on the GK 22 cotton at flowering stage shortened by 17.79%, the survivorship, fecundity, the life span of female and rm increased by 4.5%, 39.62%, 12.14% and 20.18%, respectively, compared with S3 cotton. At the seedling stage, the developmental time (from egg to adult) of B. tabaci increased by 14.14%, the life of female and rm increased by 17.46% and 1.47%, respectively. And no significant difference was detected in survivorship and fecundity of the whiteflies on two types of cottons. Moreover, under field inconstant temperature conditions, the developmental time of B. tabaci on Goukang No.22 was 13.6% shorter than that on S3 cotton. The cotton plant at flowering stage is more beneficial to the development and reproduction of B. tabaci than that cotton plants at seedling stage. Compare with non-Bt transgenic cotton, Bt transgenic cotton was more advantageous to the development and reproduction of sweet potato whitefly, B.tabaci.