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The effects of packaging on food freezing was investigated using both modeling and experimental methods. First, CFD method was employed to model the freezing condition of food in freezing chamber, including air temperature, air velocity and turbulent intensity, which was then used to calculate the surface heat transfer coefficient of food product. Empirical relations for free convection and radiation were used to simulate the heat transfer inside the air layer between food and packaging material. Fourier formula was applied to model the heat transfer inside food. Finally, an iteration scheme was used to combine all parts together. Freezing experiments were conducted in a small freezer to verify the model, which showed encouraging agreements on freezing curves of food at different locations. Packaging has a big influence on food freezing, food with different packaging differs greatly in freezing process. The thermal resistance of air layer in packaging changes in a reverse trend of food temperature drop.