Order †Ornithischia Seeley, 1887
Parvorder †Genasauria Sereno, 1986
see Clade Genasauria Sereno 1986
Nanorder †Cerapoda Sereno, 1986
see Suborder Cerapoda Sereno, 1986
Hypoorder †Euornithopoda Sereno, 1986
see Clade Euornithopoda Sereno 1986
Suborder †Ornithopoda Marsh, 1871
see Infraorder Ornithopoda Marsh, 1881
Infraorder †Iguanodontia Dollo, 1888
see Clade Iguanodontia Dollo 1888
Gigafamily †Dryomorpha Sereno, 1986
see Clade Dryomorpha Sereno 1986 [D. Madzia, V.M. Arbour, C.A. Boyd, A.A. Farke, P. Cruzado-Caballero & D.C. Evans 2021]
Megafamily †Ankylopollexia Sereno, 1986, nom. inval.
see Clade Ankylopollexia Sereno 1986
Grandfamily †Styracosterna Sereno, 1986, nom. inval.
see Clade Styracosterna Sereno 1986
1 Genus †Probactrosaurus Rozhdestvenskii, 1966
2 Hyperfamily †Iguanodontoidea Hay, 1902
see [unranked] Iguanodontoidea Hay, 1902