Abstract: This study aimed to investigate the effects of dietary sodium acetate supplementation on growth performance, serum biochemical index, skeletal muscle glucose uptake, and the expression of key genes related to protein retention in juvenile Monopterus albus. The healthy juveniles (initial body weight: 41.05±0.19g) were fed diets supplemented with 0 (Y0, control), 0.1% (Y1), 0.2% (Y2), 0.3% (Y3), and 0.4% (Y4) sodium acetate for 56d. At the end of the feeding trial, growth performance, serum biochemical index, nutritional composition of whole body, muscle glycogen content, and the expression of relevant genes in skeletal muscle were analyzed. The results showed that with the increase of dietary sodium acetate levels, final body weight, weight gain rate (WGR), protein efficiency ratio (PER), and protein retention rate (PRR) increased first and then decreased, reaching the maximum in the Y3 group and significantly higher than that in the Y0 group (P<0.05) , whereas feed conversion ratio (FCR) showed an opposite trend. The broken-line fitting analysis indicated that the optimal feed sodium acetate levels corresponding to WGR, FCR, PER, and PRR were 0.31%, 0.31%, 0.30%, and 0.31%, respectively. There were no significant differences in survival rate or condition factor among all groups (P>0.05). The serum glucose levels in the Y2, Y3, and Y4 groups were significantly lower than those in the Y0 group (P<0.05), the serum aspartate aminotransferase (AST) levels in the Y3 and Y4 groups were significantly lower than those in the Y0 group (P<0.05), and the serum total protein (TP) levels in the Y2, Y3, and Y4 groups were significantly increased than those in the Y0 and Y1 group (P<0.05), while no significant difference was observed in serum insulin and alanine aminotransferase (ALT) levels among all groups (P>0.05). There was no significant difference in moisture, crude protein, crude lipid, and ash content among groups (P>0.05), whereas muscle glycogen content increased with increasing sodium acetate supplementation (P<0.05). Gene expression analysis showed that sodium acetate significantly up-regulated the expression levels of ampkα1, ampkα2, glut4, mtor, and s6k1 genes in the muscle, with the peak value observed in the Y4 group. In conclusion, appropriate dietary sodium acetate supplementation can improve the growth performance of juvenile Monopterus albus by regulating the expression of key genes related to glucose uptake and protein retention, and based on broken-line analysis of the relationships with WGR, FCR, PER, and PRR, the optimal supplementation level is estimated to range between 0.30% and 0.31%.