A revision of the Australian freshwater mussels of the Sphaeriidae (Mollusca, Bivalvia) is given. The author distinguishes 12 species, 5 belonging to the genus Sphaerium Scopoli and 7 to the genus Pisidium C. Pfeiffer. With the exception of the cosmopolitan P. casertanum (Poli), all are Australian endemics. One species of Sphaerium (kendricki) and three of Pisidium (aslini, fultoni and science. Lectotypes are selected of hallae) are new to Sphaerinova nundinalis Iredale, Australpera mena Iredale and Pisidium etheridgei Smith. Species concepts within the Sphaeriidae and problems of their subgeneric classification are discussed. The subgenera Afropisidium Kuiper and Odhneripisidium Kuiper are relatively sharply defined, morphologically as well as zoogeographically. Lectotypes of P.(A.) gundlachi Arango and P.(A.) consanguineum Prime, both from Cuba, and earlier selected by Dr. C. Meier-Brook without publication, are designated. Afropisidium, represented in Australia by P. aslini, possibly has a Gondwanic origin. The Eurasian Odhneripisidium is not known from Australia, but may eventually be found in tropical Australia. Cyclas australis Lamarck and Pisidium semen Menke, originally described as Sphaeriidae, belong to the marine Leptonidae. Lectotypes of both are designated and figured.