ABSTRACT. – The diet of the red mullet Mullus barbatus (L., 1758) off eastern coasts of Algeria was studied between December 2007 and November 2008. A total of 573 individuals with lengths between 10 and 22 cm and of total weight ranging from 11 g to 130 g were examined. Qualitative and quantitative analyses were performed according to sex, state of sexual maturity of the predator (juveniles and adults) and seasons. The average annual index of vacuity was 37.87 % and varied significantly according to seasons (χ² = 169.91; p ≤ 0.05), sex (χ² = 28.49; p ≤ 0.05) and between juveniles and adults (χ² = 8.05; p ≤ 0.05). A total of 1491 preys (63.4 g) belonging to 11 items (Crustacea, Mollusca, Annelida, Actinopterygii, Bryozoa, Nemathelmintha, Plathelmintha, Cnidaria, Echinodermata, Porifera and Macrophyta) was recorded, which corresponds to a mean number of four preys per full gut examined. The mean prey weight per gut was 0.2 g. Statistical comparison using ANOSIM test showed that the abundance of prey changes significantly according to seasons, sex and sexual maturity. In spite of numerical and weight fluctuations of the ingested preys, statistical comparison using Spearman rank coefficient (ρ) did not show any qualitative and quantitative changes of M. barbatus diet whatever the season, the sex and the sexual maturity.