Austrostipa S.W.L.Jacobs & J.Everett is a monophyletic genus of temperate Australian native grasses that occur throughout the southern part of the continent and in New Zealand. Eight new species from Western Australia are described and illustrated here, plus two newly recorded species that are range extensions from their previously known habitats in South Australia, bringing the total number of species recorded in this state to forty-four. Detailed character notes and a key to the species and the accepted subgenera are provided. The new species are: A. anaiwaniorum A.R.Williams, A. burgessii A.R.Williams, A. everettiana A.R.Williams, A. frankliniae A.R.Williams, A. heteranthera A.R.Williams, A. koordana A.R.Williams, A. nunaginensis A.R.Williams and A. turbinata A.R.Williams. One former species (A. nullanulla J.Everett & S.W.L.Jacobs) has been reduced to synonymy with A. vickeryana J.Everett & S.W.L.Jacobs. The two species with range extensions are A. echinata (Vickery, S.W.L.Jacobs & J.Everett) S.W.L.Jacobs & J.Everett, which has been found at several sites around Esperance, and A. mundula (J.M.Black) S.W.L.Jacobs & J.Everett, which has been found in numerous small isolated coastal pockets around the south-west and up as far as Yanchep north of Perth. Five of the new species appear to be rare and isolated, including the newly discovered populations of A. echinata and A. mundula, and warrant conservation priority.