Quality of Pacific white shrimp (PWS) soaked in chitooligosaccharide-catechin (CHOS-CAT) conjugate at varying concentrations (1.0 and 2.0%, w/v) and those treated with CHOS-CAT conjugate at aforementioned concentrations with the aid of pulsed electric field (PEF) and vacuum impregnation (VI) was studied when stored at 4 °C for 15 days. Among all treatments, a lower melanosis score of 7 was found in the samples when pre-treated with PEF, followed by soaking in CHOS-CAT conjugate at 2% (w/v) with VI (CC-PV-2) than other samples after 15 days of storage (p < 0.05). Total viable bacteria, psychrotrophic bacteria, presumptive Pseudomonas, Vibrio parahaemolyticus, other Vibrio sp., H2S-producing bacteria, and Enterobacteriaceae counts of CC-PV-2 were lower than other samples at the end of storage (day 15). CC-PV-2 exhibited the lowest TVB-N and TMA-N contents, PV, and TBARS value when compared to the control and other treated samples throughout the storage (p < 0.05). Polyunsaturated fatty acids were retained at a substantial amount in the CC-PV-2 at the end of storage. In addition, next generation sequencing revealed a low percentage of spoilage bacteria such as Shewanella and Pseudomonas and pathogenic bacteria namely Vibrio sp. in the CC-PV-2. Also, CHOS-CAT conjugate showed hydrogen bonding with various targeted proteins of bacteria, as elucidated using molecular docking, verifying its bacterial inhibitory potential. CC-PV-2 had a shelf-life of at least 12 days, while the control could be kept only for 3 days. Overall, the application of CHOS-CAT conjugate with the aid of PEF and VI led to the enhanced quality and extended shelf-life of refrigerated PWS.