Arrestment responses to stimuli from Schizotetranychus nanjingensis on bamboo leaves by the predatory mites Typhlodromus bambusae and Amblyseius cucumeris were examined in the laboratory using two-choice tests. Both predator species responded to spider mite females and web-nests, but not to their feces. Furthermore, T. bambusae responded more strongly to intact web-nests than to empty web-nests, whereas A. cucumeris responded more strongly to empty web-nests.