Three new spp of Desmoscolex, found in samples from Yonge Reef, Lizard Island, Nymphe Island and between One Tree Isles and Wistari Reef are described: D. australicus sp. n., characterized by the head-shape with naked semi-circular anterior part, by the jointed cephalic setae inserted close to the anterior extremity and by the shape of the gubernaculums with less sclerotized proximal part; D. membranosus sp. n. close to D. granulatus Decraemer, 1974, but differing from it by the presence of a partly disconnected circumoral membrane and by the oval amphids not reaching the extreme anterior end; D. yongei sp. n. resembling D. americanus Chitwood, 1936, but differing from it by the longer and more slender spicules, by the presence of fine spines on the secondary rings, by the head-shape without a truncated anterior end and by the almost circular amphids. Australian specimens belonging to D. falcatus Lorenzen, 1972, and D. gerlachi Timm, 1970, are compared with the type specimens.