Abstract: This study explored the effects of combining slightly acidic electrolyzed water (SAEW) and ε-polylysine hydrochloride (ε-PLH) on the quality of refrigerated Micropterus salmoides fillets. Fishes weighing 500–800 g were cleaned after slaughtered and cut into 30±3 g fillets. Four treated groups were set up: Sterile purified water (CK), 50 mg/L SAEW (SAEW), 0.3% ε-PLH (PLH), and a mixture of 50 mg/L SAEW and 0.3% ε-PLH (MIX). Fillets were soaked in the solutions at a 1:5 (w/v) ratio for 15 minutes, drip dried, sealed in PVC bags, and stored at 4 ℃. Microbial, physicochemical, and sensory evaluations were done regularly. Results indicated that by day 12 of storage, the total bacterial count in the MIX group (6.58 lg CFU/g) remained below the maximum safety limit (7.00 lg CFU/g) stipulated by International Commission on Microbiological Specifications for Foods (ICMSF), while the CK, SAEW, and PLH groups exceeded this limit by day 8, day 12, and day 12, respectively. The MIX group exhibited significantly lower volatile basic nitrogen (TVB-N) content (13.42 mg/100g) and thiobarbituric acid (TBA) value (0.55 mg/kg) compared to individual treatment groups (P<0.05), along with the slowest pH increase (7.10). Microbial diversity analysis revealed that the relative abundance of the spoilage bacterium Pseudomonas in the MIX group (78%) was significantly lower than that in the CK group (85%) (P<0.05). Additionally, the MIX group demonstrated superior color stability (only a 6.9% decrease in L^* value and minimal change in a^* value) and texture properties (70% hardness retention) compared to individual treatments. Sensory evaluation confirmed that the MIX group maintained higher acceptability even on day 12 of storage. In conclusion, the combination of SAEW and ε-PLH effectively delayed quality deterioration in refrigerated Micropterus salmoides fillets, offering a valuable reference for processing and marketing freshwater fish ready-to-cook products in China.