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Dimethoate is an organophosphorus insecticide and acaricide that is highly efficiency to control piercing insects.In this research, dimethoate of three different rates was applied at (quarter rate 0.56 kg/ha, normal rate 2.25 kg/ha and quadruple rate 9.00 kg/ha) in cotton by soil application.The absorption and systemic distribution of dimethoate as well as control effect of mite (Tetranychus urticae Koch.) were investigated.The results proved that dimethoate was reside in cotton leaves till 45 days at normal rate and quadruple rate, and then the highest absorption level of dimethoate in cotton leaves, stems and roots were observed on day 3 for three treatments.The limits of quantification were set at 0.10 mg/kg in cotton leaf, stem, root and soil.Dimethoate absorption in cotton leaves were the highest, however, absorption in the cotton stems and roots mainly stayed at a steady lower level.The accumulation of dimethoate in young and old leaves was higher than cotyledon.In addition, the treatment of 9.00 kg/ha was a suitable concentration,dimethoate control efficiency was more higher than 50% until 7 days.Dimethoate of quadruple rate 9.00 kg/ha can efficiency control mites after soil application.