The study aimed to determine the shelf life and quality changes of red sea bream which is coated by using enriched sodium alginate (SA) with 6-gingerol (GR) during 20 days of refrigerated storage (4 ± 1 °C). Fish total volatile basic nitrogen (TVB-N), thiobarbituric acid value (TBA), K-value and pH value, sensory evaluation, TCA-soluble peptide, texture, and microbiological analyses were measured. The results indicated that alginate coating combined with 6-gingerol (SAGR) treatment delayed lipid oxidation, protein degradation, nucleotide breakdown, and inhibited microbial growth compared with the control. The efficiency was better than that of SA or GR treatment. Sensory evaluation proved the efficacy of SAGR coating by maintaining the overall quality of red sea bream during storage. Additionally, SAGR maintained better textural characteristics. Our study suggests that the use of alginate coating enriched with 6-gingerol has the potential to maintain red sea bream quality and extend its shelf life to 20 days.