Samples of Pectinariidae in the Australian Museum and Museums of Victoria, Australia were examined. Thirteen species were identified, including three additional records of previously recorded species of Amphictene and two new species, A. cercusa n. sp. and A. undulata n. sp., two species of the genus Lagis which has not previously been recorded from Australia, including a new species, L. portus n. sp., and five additional records of previously recorded species of Pectinaria and one new species, P. ningalooensis n. sp. The study revealed additional characters which are useful to identify species of pectinariids, a pair of ear-shaped lobes which are adjacent to both sides of dorsal base of cephalic veil in species of Pectinaria and Amphictene, but in Lagis they are present between the buccal cavity and lateral margin of segment 1; and a pair of ventral lappets which have not previously been described on the lateral margin of segment I in all species of pectinariids from Australia. For species where numerous individuals were available for study, we investigated how some characters, change with increasing body size. A key to all recorded species from Australia is given, but does not imply any phylogenetic relationships.