To understand the effects of feeding on brown planthopper Nilaparvata lugens (Stl) populations resistant to Imidacloprid on biological characteristics of Cyrtorhinus lividipennis (Reuter), was fed on N.lugens which was sensitive and highly resistant to Imidacloprid for 15 successive generations, respectively. Biological characteristics of C.lividipennis SNCF15 and RNCF15 were studied. The results showed that the percentage of emergence did not vary significantly between the two colonies during egg stage, nymphal stage and adult stage, as well as every period of the whole life. Compared with RNCF15 colony,SNCF15 colony had a significantly longer egg laying phase and higher spawning rate, and a relatively higher egg hatching rate as well as the survival rate of nymphs, but a shorter egg period.