[Objectives]  To determine the compatibility of eight common pesticides with Lecanicillium lecanii JMC-01, and the toxicity of combinations of each pesticide and L. lecanii JMC-01 to Bemisia tabaci nymphs. [Methods]  The effects of each of eight pesticides on the spore germination and sporulation of L. lecanii, and their LC₅₀ and co-toxicity coefficients with respect to B. tabaci nymphs, were tested using the coating and dipping methods. [Results]  The growth inhibition rate, spore germination inhibition rate and sporulation inhibition rate of L. lecanii decreased with pesticide dilution factor. The bio-pesticide lspinetoram, veratrine and azadirachtin were the most compatibile and had the best synergistic effect with L. lecanii. The inhibition rates of spore germination for 10-fold dilutions of lspinetoram, veratrine and azadirachtin were 20.02%, 16.41%, and 15.38%, respectively, and sporulation inhibition rates were 17.77%, 15.90%, and 14.96%, respectively. Mycelial growth inhibition rates for the above pesticides were 9.96%, 8.87%, and 9.74%, respectively. The best synergistic control was achieved using a combination of azadirachtin and veratrine with L. lecanii. Maximum CTC was 315 and 302, respectively. [Conclusion]  Selecting pesticides that are compatibile with L. lecanii, and that have a high co-toxicity coefficient at low doses, can significantly reduce the amount of pesticide required to control B. tabaci in greenhouses.