A total of 262 fish, crustacean and mollusc species, representing the most important animals used in aquaculture worldwide are listed. This list has been derived primarily from those reported by Member Countries to FAO in the aquaculture production statistics with the addition of other species reported in other sources as being important. For each one of the listed species, family, scientific name, common name, environment, total production as reported by FAO, geographical distribution and pro duction by continent are given. Under geographical distribution, the list distinguishes between native or introduced species. Each list of the major animal group is completed by notes providing information on inconsistencies which have been found between the different sources consulted during the preparation of the list. All data are summarized in a final table. Asia, which produces about 85% of world aquaculture production, is the continent where introduced species have less importance. Instead, introduced species form the major part of crustacean production in Europe and fish production in South America and Oceania. A very limited number of species (31) account for 95% of the total production reported to FAO at the species level. Eleven of these species belong to the Cyprinidae. The number of species reported to FAO has increased in the last eleven years but not as much as would be expected as an outcome of the effort of researchers and farmers in experimenting with new s pecies suitable to aquaculture.