The work aims to study the relationship between the Expandable Polyethylene (EPE) net heat sealing quality and heat sealing parameters (EPE tensile rate, diameter of electric heating wire, temperature of electric heating wire and time of heat sealing), and analyze the characteristics of the heat sealing process of EPE nets, so as to lay a foundation for the design of EPE net heat sealing packaging machines. The electrothermal characteristics of nickel-chromium wires under different current were studied by experiments and electrothermal coupling simulation, and current and temperature models were established. At the same time, three-factor and three-level full factor tests were carried out to analyze and determine the optimal heat sealing parameters of the EPE net. The simulated transient temperature was more accurate than that measured by temperature sensor. The lower the tensile ratio of the EPE net, the greater the heat sealing strength. The optimum heat sealing parameters of the EPE net were as follows:the diameter of electric heating wire was 2 mm, the heat sealing temperature was 130 ℃, and the time of heat sealing was 4 s. The thermal inertia of the temperature sensor causes the measured value of the electric heating wire to lag behind the actual value, which is especially prominent in the process of rapid temperature rise. By establishing the electrothermal coupling model, the electrothermal characteristics of the electric heating wire can be characterized more accurately, which provides a method for the prediction of transient temperature. The research of the EPE net heat sealing technology can provide a more universal and efficient packaging method for the protection of fruit EPE net sleeve packaging.