In this study, we investigated the inactivation of human norovirus (HuNoV) surrogate Murine norovirus (MNV-1) by X-ray in whole-shell Atlantic oysters (Crassostrea virginica). We also investigated the effects of X-ray treatments on the survivability, inherent microbiota, color, and firmness of treated whole-shell Atlantic oysters during storage at 5 o C for 20 days. Plaque assays revealed that X-ray significantly reduced the population of internalized MNV-1 in live oysters from 4.3 ± 0.4 log PFU g-1 to 3.6 ± 0.5, 3.2 ± 0.2, 2.8 ± 0.2, and 2.5 ± 0.1 log PFU g-1 , by 1.0, 2.0, 3.0, and 4.0 kGy X-ray, respectively. The population of MNV-1 was reduced to less than 2.0 log PFU g-1 at 5.0 kGy X-ray. The survivability of live oysters was not significantly affected by treatment with 1.0 and 5.0 kGy X-ray, in comparison with the control, for up to 15 and 10 days, respectively, during storage at 5°C. Treatment of whole-shell oysters by 5.0 kGy X-ray significantly reduced the inherent microbiota and kept them lower than the control until day 20. No significant effect of X-ray treatment on oyster color or firmness was detected.