Nine new species and one new subspecies of Calothamnus from Western Australia are described, namely C. graniticus, C. tuberosus, C. formosus, C. formosus subsp. rigidus, C. hirsutus, C. brevifolius, C. aridus, C. macrocarpus, C. kalbarriensis and C. borealis.. A new combination, C. graniticus subsp. leptophyllus, is also provided, based on C. torulosus Schau. var. leptophylla Benth. The affinities of the new species are considered. In addition, a key is provided to all species of Calothamnus presently recognized.