Abstract: The diurnal rhythm of oxygen consumption and effects of body weight and temperature on oxygen consumption rate of Sparus macrocephalus were examined under a flowing-water apparatus. The results revealed that the oxygen consumption rate of S.macrocephalus exhibits an increase with the rise of water temperature but a decrease with the increment of body weight. The rate of oxygen consumption varied with the alternation of day and night. The highest oxygen consumption rate was 3.16±0.26 μg·(g·min)^-1 at 11: 00pm, and the lowest oxygen consumption rate 0.74±0.59 μg·(g·min)^-1 at 7: 00am. The mean oxygen consumption rate was 1.98±0.84 μg·(g·min)^-1 at day and 1.96±0.63 μg·(g·min)^-1 at night. The results showed that the change of metabolism level of S.macrocephalus is not significantly between day and night (n=10, t=0.034 < t_0.05)。