The chitosan nano-SiO2 composite membrane was prepared and its CO2 permeability was studied for fresh-keeping strawberries. The results showed that the best contents of chitosan, nano-TiO2, and glacial acetic acid were 2 g, 0.07 g, and 1.4mL, respectively. The CO2 permeability of the optimized membrane was 0.0909 g/d. After stored for 6 days at room temperature, strawberries coated with the optimized membrane had lower decay index by 5.1% than that uncoated with membrane. After 11-day storage at 4 ℃, the decay index of strawberries was 23.9% lower than that of the strawberries without coating with membrane. The result proved that the storage period of strawberries was prolonged at room temperature and low temperature by coating with optimized membrane.