Samples from two populations of the citrus red mite collected from citrus orchards were assayed for susceptibility to abamectin, chlopyrifos, fenpropathrin and pyridaben. The results indicate that the Beibei population displayed a 3, 3 and 22fold resistance ratio, respectively, to chlopyrifos, fenpropathrin and pyridaben compared to a susceptible strain. The Wanzhou population exhibited a 2, 35, 10 and 2fold resistance ratio, respectively, to the same pesticides. Enhancement of CarE activity was involved in resistance to chlopyrifos in both populations. Inhibition of chlopyrifos activity differed between the two mite populations and was stronger in the Wanzhou population than the susceptible strain.