The dispersal responses of Tetranychus viennensis Zacher were studied when the mite was exposed to various sublethal concentrations of methyl parathion and fenpyroximate on peach under laboratory conditions. The study was conducted under direct exposure of mites to pesticides and exposure to their residues. A significant increase in dispersal of this mite was observed as concentrations of pesticides increased from LC₅ to LC₅₀. At LC₂₅ and LC₅₀, fenpyroximate caused greater dispersal under direct exposure than methyl parathion, but there were no significant differences under exposure to their residues. Walk-off was the predominant mode of dispersal.