Abstract: Chemokine receptor is a kind of transmembrane receptor (GPCR) which includes seven hydrophobic transmembrane structures.Studies have shown that chemokine and their receptors play an important role in inflammatory reaction, pathogen infection, wound repair, tumor formation and metastasis and so on.But, the role of chemokine receptors in teleost fish, especially in fish antiviral remains unclear.In this study, the ORF sequence of CC chemokine receptor 6a (CCR6a) gene was cloned from tissue of orange-spotted grouper, and its sequence and evolutionary relationship were analyzed.At the same time, tissue distribution, subcellular localization and antiviral function of this gene were studied.The results showed that the full length of ORF sequence of CCR6a gene in oblique grouper was 1 131 bp, encoding 376 amino acids.Evolutionary tree analysis showed that orange-spotted grouper CCR6a was the closest relative between giant grouper.Quantitative real-time PCR (RT-qPCR) detection of CCR6a tissue distribution found that CCR6a was high expression in immune tissue like kidney, gill, and skin.Subcellular localization showed that CCR6a was distributed in membrane.Overexpression of CCR6a in GS cells could significantly inhibit the replication of red-spotted grouper nervous necrosis virus (RGNN).These results would help to understand the role of fish chemokines in viral infections.