Abstract: Abstract: Packaging materials can be widely used to protect food products from contamination while in storage. In this study, the sterilization process was simulated and optimized using hydrogen peroxide (H2O2) solution atomized aerosol on the inner surface of a gable-top carton. The efficacy of hydrogen peroxide solution was evaluated with the different size boxes in the sterilization process. The process, principle, and influencing factors of solution atomization were analyzed using the sterilization process of hydrogen peroxide in the packaging materials of the roof box packaging machine. Finally, the optimal scheme was provided for uniform sterilization. The Euler-Lagrange model was selected to simulate the atomization process of an air-assisted nozzle. A comparison was also made to clarify the effects of atomization times and air pressure on the atomization quality. Specifically, the Droplet Sauter average diameter decreased, whereas, the atomization distance increased with the increase of atomization time. There was an increase in the spray distance, angle, and range, with the increase in air pressure. As such, a more uniform liquid atomization was achieved during this time. The different simulation conditions were compared with the actual spray debugging, in order to observe the spray shape. At the same time, the spray angle, and spray distance were measured under different conditions. It was found that the errors between the measured and the simulated values were within 15%, indicating the excellent performance of the simulation. The air-assisted spray model was then applied to the sterilization process, combined with the structural simulation of gable-top cartons with different specifications. There was a significant effect of carton specifications on the distribution of atomized droplets, especially in the bottom position. Specifically, the low height of the 250 mL carton led to a large number of droplets gathering on the bottom surface of the carton. There was a more outstanding increase in the spray height, and the atomized solution escape. By contrast, the solution aggregation of the bottom surface was reduced for the more uniform distribution of the side solution. Therefore, the optimal spray height was achieved for uniform and safe sterilization, indicating the higher concentration of H2O2 residues on the bottom surface. In 1 000 mL cartons, almost no droplets were attached to the bottom end and bottom surface, due to the higher height than that of the rest. In this case, the distribution of the liquid film was more uniform, whereas, the higher thickness was obtained to increase the atomizing air pressure. Therefore, the optimal air pressure was recommended to appropriately increase for better sterilization. More importantly, there was insufficient bottom of the carton sterilization. The numerical model of hydrogen peroxide sol sterilization can be expected to combine with different process parameters, thereby to output the simulation for higher sterilization efficiency. At the same time, the process parameters were optimized for the different cartons. The finding can also provide a strong reference for the process design of aerosol sterilization on the packaging materials, particularly diversified size roof carton filling machine in the future.