The work aims to establish the gas exchange model of heat sealing micropore channel in packaging bags and verify the model by experiments. The gas exchange model of heat sealing micropore channel in packaging bags was established based on poiseuille's law. The model was verified by changing the related parameters, such as pore channel diameter, pore length and inner and outer pressure difference. When the mircopore diameter were 100, 140 and 180 μm, the error between the gas exchange experimental value and model value basically maintained within 5%. With the increase in channel diameter and inner and outer pressure difference, the micropore channel gas exchange capacity was increased and changed obviously. For the micropore channel with initial inner and outer pressure difference and certain pore diameter, changing the length of pore had certain effects on gas exchange. The predicted value of the established gas exchange model achieves high conformity with the experimental value.