An account is given of the lichen family Graphidaceae in Australia. The morphology, chemistry and history of the family in Australia are discussed. Sixteen genera containing 129 taxa, including 127 species and two varieties, are reported, distributed as follows: Acanthothecis Clem., 3 species; Carbacanthographis Staiger & Kalb, 2 species; Diorygma Eschw., 8 species; Dyplolabia A. Massal., 1 species; Fissurina Fée, 10 species; Glyphis Ach., 3 species; Graphis Adans., 54 species; Hemithecium Trevis., 8 species; Leiorreuma Eschw., 4 species; Phaeographis Mull. Arg., 19 species; Platygramme Fée, 8 species; Platyrhecium Staiger, 1 species; Sarcographa Fée, 4 species; Sarcographina Müll. Arg., 1 species; Thalloloma Trevis., 1 species and Thecaria Fée, 2 species. The synonymy, chemistry, distribution and ecology of each species are reported. The majority of species (87%) either lack lichen compounds (43%) or contain norstictic (26%) or stictic (18%) acids. Twelve other lichen compounds occur less frequently.