Lowry & Stoddart  established the lysianassoid amphipod family Amaryllididae. In the following paper the systematics of the diverse Australian amaryllidid fauna is presented. All amaryllidid genera are revised and rediagnosed and a key to genera is provided. Five genera and 23 species are recorded from Australian waters. Bathyamaryllis is recorded from Australia for the first time and new evidence indicates that Amaryllis is confined to Australia and possibly the New Zealand area. Two subfamilies (Amaryllidinae and Vijayiinae), three genera (Bamarooka, Devo and Wonga) and 20 species are new. The new species are Amaryllis carrascoi, A. croca, A. dianae, A. kamata, A. keablei, A. migo, A. moona, A. olinda, A. philatelica, A. quokka, A. spencerensis, Bamarooka anomala, B. dinjerra, B. endota, B. kimbla, B. tropicalis, Bathyamaryllis kapala, Devo dubuc, D. grahami and Wonga wonga. Distribution, depth and habitat notes are given for all species. Amaryllidids form two natural groups: a presumed free-living deep-water group with a subquadrate mouthpart bundle (Vijayiinae) and a presumed commensal shallow-water group with a subconical mouthpart bundle (Amaryllidinae). Except for Vijaya tenuipes the vijayiines are exclusively found in the deep seas of the North and South Atlantic and South Pacific Oceans. The amaryllidines are found in shallow temperate and tropical seas of the southern hemisphere. The largest diversity of genera and species is currently known from Australian waters, but the African and South American faunas have not been adequately described.