Abstract: In order to explore the spatial-temporal expression characteristics of miR-125b and the effect of starvation on its rhythm in Siniperca chuatsi, real time quantitative PCR was used to analyze the expression of miR-125b in the embryos of different developmental stages, different tissues and the rhythmic expression after 5 days of starvation. The results showed that the expression of miR-125b was highest in red muscle followed by myocardium, whereas lower in other tissues. The expression of miR-125b in the embryonic development stage showed decreased in the early embryos and then increased in hatching larvae. The expression was at the highest level during the 2 cell stage to 32 cell stage, significantly deceased after entering the blastula stage, and remained low level until heart beating stage, then began to be up-regulated at hatching larvae stage. In normal feeding, the expression of miR-125b in white muscle showed no obviously circadian rhythm. After 5 days of starvation, the expression of miR-125b showed obvious rhythmic oscillation, which rhythmic oscillation was higher in the day and lower in the night, in white muscle. In normal feeding and starvation conditions, the expression of Arntl2 was opposite to miR-125b, and the expression of Arntl2 was significantly increased after treatment with miR-125b antagomir. The results indicated that the expression of miR-125b was maternal in the embryo, suggesting that the target genes regulated by miR-125b may inhibit early embryonic development and have a wide range of biological functions. Furthermore, the results indicated that miR-125b could participate in regulating adaptive physiological metabolism function of S. chuatsi muscle by negatively regulating the expression of circadian gene Arntl2 under starvation stress.