Intestinal microbiota plays a vital role in the sustenance of fish well-being, promoting fish development, resistance to bacterial invasion, regulation of energy absorption, and lipid metabolism. In fish science, due to their large number of varieties, differences in their feeding habits, and complicated and changeable environmental conditions, the studies on their intestinal microbiota face enormous challenges. In this study, the combination of chromatography and mass spectrometry and high throughput sequencing was utilized in summarising the composition of intestinal microbiota and metabolite profiles in the gut of juvenile cobia fed with basal diet (control) and indigenous isolates Bacillus sp. RCS1, Pantoea agglomerans RCS2, and Bacillus cereus strain RCS3 mixture supplemented diet.