Abstract:28 species of parasitic wasps of Dryocosmus kuriphilus were found in Shandong Province， which almost belong to chalcidoidea and ten of them are more important．A key to the species is provided．The parasitic wasps are either monoparasitic or polyparasitic，either protoparasitic or epiparasitic，either ectoparasitic or endoparasitic．4—5 species of them are more significantly affect the change of the population of Dryocosmus kuriphilus which occupy a certain niche in different environments．Torymus sinensis K．Which is the most important parasitic wasp leads the periodical change of population density of Dryocosmus kuriphilus．