Abstract: Laboratory toxicity test and field efficacy of three acaricides on Panonychus citri on black plums were conducted.The results showed that the laboratory LC50 of avermectins,pyridaben and avermectins+propargite on P.citri were 0.1596 mgL-1,0.9752 mgL-1 and 23.7307 mgL-1,respectively.Avermectins had the best poisoning effect on the pest.The field efficacy of 5.12 mgL-1 avermectins,64.00 mgL-1 pyridaben or 280.00 mgL-1 avermectins+propargite on P.citri all exceeded 90.00%.The three pesticides all had high lethality to the pest with no phytotoxicity.The b-values of the toxicity regression equations for the three acaricdes differed.The P.citri population sensitivity distributed most evenly with avermectins+propargite,followed by pyridaben and avermectins.It appeared that the laboratory LC50,field efficacy and b-value on the toxicity regression equation could be used as the criteria to evaluate P.citri's sensitivity to acaricides on black plums.