The Australian; New Zealand, and Papua New Guinean representatives of the lichen genus Xanthoparmelia are revised. Keys and descriptions for the 111 species are given, and the chemistry, distribution, ecology, and taxonomic affinities of each species are discussed. Xanthoparmelia alexandrensis, X. alternata, X. aurifera, X. centralis, X. concomitans, X. crateriformis, X. cravenii, X. dissitifolia, X. donneri, X. dubitata, X. examplaris, X. ferruma, X. filsonii, X. gongylodes, X. hypomelaenoides, X. immutata, X. iniquita, X. laxencrustans, X. louisii, X. nashii, X. norpumila, X. parvoincerta, X. rogersii, X. rupestris, X. spargenosa, X. tegeta, X. verdonll, X. verrudformls, X. vicaria, and X. xerophila are described as new. New names are given to Xanthoparmelia eilifii and X. succedans (formerly Parmelia dahlii, P. adpressa respectively). New combinations in the genus are proposed for Parmelia amplexula Stirton, P. antleriformis Elix, P. bellatula Kurok. & Filson, P. bungendorensis Elix, P. congesta Kurok. & Filson, P. consociata Elix, P. constipata Kurok. & Filson, P. dayiana Elix & P. Armstr. . P. elaeodes Elix, P. erosa Elix & P. Armstr., P. everardensis Elix & P. Armstr., P. exillima Elix, P. flindersiana Elix & P. Armstr., P. glareosa Kurok. & Filson, P. incerta Kurok. & Filson, P. incrustata Kurok. & Filson, P. conspersa v. laxa f. isidiigera Mull. Arg., P. conspersa v. stenophylla f. isidiosa Mull. Arg., P. mannumensis Elix, P. metaclystoides Kurok. & Filson, P. nebulosa Kurok. & Filson, P. neotinctina Elix, P. norconvoluta Elix & P. Armstr. , P. pertinax Kurok. & Filson, P. phillipsiana Filson, P. praegnans Elix & P. Armstr., P. pseudoamphixantha Elix, P. pseudohypoleia Elix, P. pumila Kurok. & Filson, P. pustuliza Elix, P. remanens Elix, P. reptans Kurok., P. streimannii Elix & P. Armstr., P. terrestris Kurok. & Filson, P. ustulata Kurok. & Filson, P. willisii Kurok. & Filson, and P. xanthosorediata Elix. In total 117 species are recognized from Australia, 47 from New Zealand, three from Papua New Guinea, one from Fiji, and one from Norfolk Island.