The predatory potential of Geocoris pallidipennis (Costa) on Adelphocoris lineolatus (Goeze) was assessed in the laboratory.G.pallidipennis began to prey on A.lineolatus after the latter had entered the 3rd instar.The predatory responses of G.pallidipennis to A.lineolatus were of the Holling Ⅱ type.Predation of G.pallidipennis on A.lineolatus declined with increasing developmental stage of the latter,but increased with its own developmental stage.During one 24 h period,adult female G.pallidipennis could,at most,consume 37.88 1st instar nymphs of A.lineolatus.In addition,the predation rate gradually increased with temperature from 15 ℃ to 35 ℃,being 1.78 times higher at 35 ℃ than at 15 ℃.These results indicate that G.pallidipennis is a potential biological control agent for A.lineolatus.