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A trial was undertaken to estimate the protein requirement of sharpsnout sea bream (Diplodus puntazzo) and the protein sparing of dietary lipids. Ten diets were formulated to contain 5 protein levels (ranging from 15 to 55%) and two lipid levels (12 and 18%). Each diet was assigned to duplicate groups of 15 fish with a mean individual body weight of 49.3g. A quadratic model was used to adjust weight gain and N retention (gkgABW⁻¹day⁻¹) to dietary protein levels. Based on that model, optimum dietary protein requirement was estimated to be 42.9% for maximum weight gain and 43.8% for maximum N retention, corresponding to a protein intake of 7.68gkgABW⁻¹day⁻¹. Protein requirement for maintenance was estimated to be 0.71gkgABW⁻¹day⁻¹. Dietary lipid level improved protein utilization efficiency but did not affect protein requirement. Whole-body protein content increased with dietary lipids and protein …