Effects of vacuum and modified atmosphere packaging (MAP) on microbial flora, pH, total volatile basic nitrogen (TVB-N), trimethylamine (TMA-N), the exudates and sensory attributes in Pacific white shrimp (Litopenaeus vannamei) during controlled freezing-point storage at −0.8°C for a period of 14 days were investigated. The results indicated vacuum packaging (VP), 40%CO₂/30%O₂/30%N₂ (MAP1) and 75%CO₂/10%O₂/15%N₂ (MAP2) were more effective for inhibiting growth of Aeromonas spp., Pseudomonas spp., H₂S-producing bacteria (including Shewanella putrefaciens) and Enterobacteriaceae and decreasing TVB-N and TMA-N contents as compared to air packaging (AP). pH values of VP and MAP2 samples were significantly (P < 0.05) lower than those of AP. Formation of exudates under AP, VP, MAP1 and MAP2 increased during the storage and the value was higher with the increase of CO₂ levels. Sensory evaluation indicated that the shelf-life of fresh Pacific white shrimp got extended and reached 7 days under VP, 9 days under MAP1 and 11 – 12 days for the optimum MA-packaged under MAP2 as compared to 4 days' shelf-life under aerobic storage.