Abstract: Host performance of whitefly,Bemisia tabaci on Phaseolus vulgaris,Hibiscus mutabilis,Hibiscus rosa-sinensis and Nicotiana tabacum were evaluated by the models developed previously.The results indicated that whitefly populations were able to improve the host performance dramatically since continuously feeding on particular host species,but the improving process was different among the host plants.With the host transferring experiments,the improved host performance by accumulation of feeding experience could not inherit,and the host performance would return to primary level as long as disappearing selection pressure.it was implicated that the whitefly populations could be able to adjust their host performance and have its host adaptation rapidly without any transformation of genetic structure.