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Galectin-8 is a member of the galectin family, and binds with β-galactoside by specific recognition with many biological functions. The present study was conducted to investigate Galectin-8 sequence characterization, its tissue distribution, and the effect of dietary ferulic acid（FA) supplementation on the Galectin-8 gene expression in hybrid grouper（Epinephelus fuscoguttatus ♀ × E. polyphekadion ♂). The technology of rapid amplification of cDNA ends（RACE）was utilized to obtain the full length（1 368 bp）of hybrid grouper Galectin- 8 cDNA for the first time. The cDNA was composed of 5' untranslated region（5' UTR）（16 bp), 3' UTR（394 bp), and open reading frame（ORF）of 960 bp that encoded 319 amino acids. The amino acid sequence of galectin-8 possessed two carbohydrate recognition domains （CRDs）at N- and C- terminus composed of 136 and 133 amino acids, respectively, which were connected by a linker peptide of 36 amino acids and contained two conserved H-NPR and WG-EE motifs. Homology and phylogenetic tree analysis indicated that hybrid grouper Galectin- 8 demonstrated the highest identity（98.43%）with E. fuscoguttatus, and was clustered with other teleosts. Based on RT-qPCR, tissue distribution analysis revealed that Galectin-8 showed the highest expressions in the spleen, followed by mid kidney, heart, intestine, liver, head kidney, and gill, yet the trace expression in the brain, stomach, skin, and muscle. Moreover, dietary FA supplementation at level of 40-320 mg/kg considerably up-regulated the Galectin-8 transcriptional level of the intestine, liver, head kidney, and spleen in hybrid grouper（P < 0.05), which suggested that FA served as an immunostimulant to improve its innate immunity. Nevertheless, Galectin-8 immune functions of the hybrid grouper are unclear, and therefore further studies are needed to illustrate its role in defense against pathogen invasion. [ABSTRACT FROM AUTHOR]