The diet composition of the Atlantic lizardfish Synodus saurus, caught on sandy bottoms of the north-western coast of Sicily (southern Tyrrhenian Sea) is described. The stomachs of 224 specimens (from 73 to 280 mm TL) were collected between June 2005 and May 2006. The analysis of stomach contents showed that this species is almost exclusively piscivorous. Unlike other benthic predators of the study area, it mainly feeds on pelagic school-forming fish, such as Clupeidae, Engraulidae and Myctophidae and juveniles of Sparidae and Centracanthidae, and benthic prey play a secondary role. The diet of S. saurus is related to the seasonal availability of resources, depending on the occurrence of juveniles of several species and on the migration of pelagic fishes in the study area. There were no significant changes in prey items between predator length groups, but a positive, significant linear relationship between prey size and predator size was recorded.