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In experimental culture conditions in tanks, the effect of weight ( W: 11-452 g) and temperature ( T: 14-29°C) on the growth rate (SGR, % bw day) and maximum daily food intake (SFR, % bw day) in sharpsnout sea bream ( Diplodus puntazzo) was studied. The possible combined effect of both independent variables ( W and T) was also analyzed by multiple regression analysis, fitting the data to the equation Ln Y = Ln a + b Ln W + cT + dT + eT Ln W. Both SGR and SFR, and therefore feed efficiency (FE = SGR/SFR), were significantly influenced by the interaction between temperature and weight and may be expressed by means of the following equations: Ln SGR = −6.1705 + 0.5809 T − 0.0087 T − 0.0249 T Ln W ( $$ R_{\text{adj}}^{2} $$ = 0.949; ANOVA P < 0.0001); Ln SFR = −4.8257 + 0.4425 T − 0.0063 T − 0.0163 T Ln W ( $$ R_{\text{adj}}^{2} $$ = 0.964; ANOVA P < 0.0001).The results suggest that the optimum temperature for SGR and FE ( T and T), and the temperature at which the maximum SFR ( T) is reached, decreases with body weight, in accordance with the equations: T = 33.297 − 1.435 Ln W; T = 29.332 − 1.890 Ln W; and T = 34.941 − 1.304 Ln W, respectively. In this way, T is 28.4, 26.7, and 24.7°C; T is 30.5, 28.9, and 27.1°C and T is 22.9, 20.6, and 18°C for 30, 100 and 400 g body weight, respectively. [ABSTRACT FROM AUTHOR]