Neoseiulus bicaudus (Wainstein) (Acari: Phytoseiidae) is a native predatory mite species in Xinjiang, China, and a biological control agent for some small pests, such as Tetranychus turkestani (Acari: Tetranychidae) and Thrips tabaci (Thysanoptera: Thripidae) in greenhouse. However, little is known whether N. bicaudus could be an effective natural enemy of Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae). A series of laboratory and greenhouse experiments were conducted to evaluate the efficiency of N. bicaudus on B. tabaci. The present data showed that each stage of N. bicaudus demonstrated type II functional response when fed on B. tabaci. The adult females showed the highest consumption rate and attack rate, and the shortest handling times were obtained when they preyed on eggs and 1^st instar nymphs. The 1^st instar of B. tabaci was preferred for the feeding of N. bicaudus adult females than eggs, followed by 2^nd instar nymphs of B. tabaci. Under greenhouse conditions, this predator effectively suppressed the population growth of B. tabaci throughout the experimental period. Accordingly, N. bicaudus could be an efficient predator for B. tabaci.