Body size, development, longevity, fecundity and survivorship of Bemisia tabaci (Gennadius) biotype B and Trialeurodes vaporariorum (Westwood) on cotton (Gossypium hirsutum L., var.Simian 3′), cucumber (Cucumis sativas L., var. Beijing 202′), eggplant (Solanum melongena L., var. Beijing 7-leaf′), and tomato (Lycopersicum esculentum Mill., var. Jiafen 10′) were studied at 27 ( 1℃, RH 75% and a photoperiod of 14∶10 (L∶D) h in the laboratory. We found that first and second instars of B. tabaci were significantly larger than the correspondent stages of T. vaporariorum on the same host plants. The sizes of third instars and pupae of the two species varied among host plants. The developmental times of T. vaporariorum from egg to adult were 197, 194, and 208 d on cucumber, eggplant, and tomato, respectively, which were significantly longer than those of B. tabaci, 17.3, 17.6, and 18.6 d, on the same host plants, respectively. The adult females of B. tabaci lived 31.2 d on cucumber and 32.1 d on tomato, which were longer than those of T. vaporariorum on the same host plants (26.0 d on cucumber and 24.9 d on tomato). The fecundities of B. tabaci on cotton, cucumber and tomato were 122.2eggs, 220.2eggs, and 266.5eggs per female, respectively, which were significantly greater than 97.1eggs, 186.6eggs, and 197.1eggs per T. vaporariorum female on the same host plants, respectively. Overall survival rates of B. tabaci from egg to adult on cotton, cucumber, eggplant, and tomato were 67.9%, 77.8%, 67.8%, and 59.0%, respectively, whereas those of T. vaporariorum were 62.2%, 67.2%, 64.4%, and 661% on the same host plants, respectively. We concluded that B. tabaci is generally superior to T. vaporariorum in many biological parameters, and it more likely outbreaks on the same host plants under the same environmental conditions as T. vaporariorum.