The fossil nautiloids described in this paper were collected in 1984 and 1985 from Lunshan, Jurong in Jiangsu; there the Ordovician strata are well developed and may be divided in descending order into seven formations as follows:Upper Ordovician: Wufeng Formation Tangtou FormationMiddle Ordovician Pagoda Formation Lower OrdovicianKuniutan FormationDawan FormationHunghuayuan FormationLunshan FormationThese nautiloids comprise 36 species belonging to 13 genera (including one new genus and 11 new species), namely,Middle OrdovicianPagoda FormationSinoceras chinense (Foord), Michelinoceras changjiangense Chen, densn (Y), M. paraelongatum Chang.Lower OrdovicianKuniutan FormationRhynchorthoceras jurongense sp. nov., R. lunshanense sp. nov., Dideroceras wahlenbergi (Foord), D. holmi Flower, Michlinoceras irregulare sp. nov., Kotoceras gaoluncunense sp. nov.Dawan Formation.Cochlioceras yantzeense Chang, Chisiloceras ichangense Wang, C. yaoshanense Qi, C. changyangense (Chang), Protocycloceras deprati Reed, P. hupehcnse (Shimizu and Obata), P. sichuanense Wang, P. remotum Lai, P. gangshanense sp. nov., P. siphosedimentum Pan, P. chaoi sp. nov., P.shishantouense sp. nov., P. gaojiabianense sp. nov., Changyangoceras gaojiabianense sp. nov., Gangshanoceras jurongense gen. et sp. nov., G. densum gen. et sp. nov., Michelinoceras cf. dayongense Lai, Troedssonella lunshanensis sp. nov., Mesosendoceras leei (Y), Vaginoceras peiyangense malukonense Chen, Dideroceras mui (Chang), D. gaoluncunense sp. nov.