Abstract:The numbers of Emposaca flavescens(Fab.) and its natural enemies in three fruit plants were compared using T-test, cherry field and pear field showed a highly significant difference in Misumenops tricuspidatus and significant difference in Emposaca flavescens(Fab.) Harmonia axyridis and Tetragnatha maxillosa,the amounts of which in cherry field were apprently higher than that in pear field,cherry field and apricot field showed a significant difference in Misumenops tricuspidatus and Erigonidium graminicola and a basal significant difference in Harmonia axyridis Tetragnatha maxillosa and Emposaca flavescens(Fab.),the amounts of which in cherry field were apprently higher than the apricot field excep the Emposaca flavescens(Fab.).Pear field and apricot field showed a significant difference in Erigonidium graminicola and Emposaca flavescens(Fab.), the amounts of which in the aricot field were apprently higher than the pear field. Relevancy of Erythroneura sudra with its natural enemies was studied by using grey systematic analysis. The results showed that As for the quantity of the natural enemies, the major natural enemies of Emposaca flavescens(Fab.) was Tetragnathidae, Erigonidium graminicola, Therdionoctomaculatum and Chrysopa sinica,while for the quantity of the ideal dominant natural enemies,the natural enemies which highly associated were Misumenops tricuspidatus, Harmonia axyridis, Erigonidium graminicola and Chrysopa sinica. As for the ecological niche analysis, both the temporal and horizontal niche overlaps were Harmonia axyridis, Erigonidium graminicola, Misumenops tricuspidatus and Tetragnatha maxillosa，while Both the temporal and horizontal niche which highly associated with the Emposaca flavescens(Fab.) were Harmonia axyridis, Misumenops tricuspidatus Erigonidium? graminicola and Tetragnathidae. It can be concluded from the Synthetical ordered analysis that the main natural enemies were Harmonia axyridis、Erigonidiumgraminicola、Misumenops tricuspidatu and Tetragnathidae.