Hydrodeoxygenation (HDO) of oxygen-rich bio-oils from municipal solid waste offers a route to sustainable hydrocarbons, but efficient deoxygenation remains challenging. In this study, oil obtained from the co-pyrolysis of food waste (FW) and polyethylene terephthalate (PET) was upgraded using a series of Ni/CexMo1-xO2 (x= 0.5, 0.2 and 0.8) composite oxide catalysts. Co-pyrolysis experiments at different FW/PET ratios showed that the 50:50 feedstock produced oil with the highest oxygen content (32 wt%), which was selected for catalytic upgrading. Among the synthesized catalysts, Ni/Ce₀.₅Mo₀.₅O₂ exhibited the best catalytic performance during HDO at 350 °C and 35 bar H₂, achieving 89.5% conversion and 94.41% selectivity toward oxygen-free compounds. In addition, complete removal of highly oxygenated and nitrogen-containing compounds was achieved over the optimized catalyst. Comprehensive characterization using XRD, O₂-TPD, H₂-TPR, NH₃-TPD, HR-TEM, FE-SEM, and XPS demonstrated that the superior performance of Ni/Ce₀.₅Mo₀.₅O₂ originated from its high oxygen vacancy concentration, enhanced oxygen mobility, optimized acidity, and highly dispersed Ni nanoparticles. The synergistic interaction between Ce and Mo species promoted hydrogen activation and efficient C–O bond cleavage, thereby enhancing deoxygenation efficiency and hydrocarbon formation. Optimization studies revealed that a feed-to-catalyst ratio of 1/5 and a reaction temperature of 350 °C provided the most favorable balance between hydrocarbon selectivity and catalyst stability. The catalyst also showed excellent reusability over four consecutive cycles with only minor deactivation and low coke deposition (1.1%). Furthermore, continuous fixed-bed reactor experiments demonstrated superior performance compared with the batch reactor, increasing the oxygen-free fraction from 94.41% to 98.88% and aromatic hydrocarbon selectivity from 85.47% to 94.58%.