Using micromill, discrete carbonate powders from the otolith of Argyrosomus argentatus were sampled along the growth band, and high-resolution stable isotope profiles were obtained. The ${delta}^{18}O$ and ${delta}^{13}C$ values are increasing gradually from the core to the margin. However, such increases do not seem to be attributed to the environmental property changes during the growth, but to the dominant effect of metabolic carbons during the early growth, and then, the isotopic composition seems to be equilibrium to the environmental condition. This paper allows the diverse applicability of high-resolution isotope research to the fish otoliths in the future.