The infrared feature of electric heating film in natural environment is discussed, with the focus on the impact of different heat properties. On the basis of finitedifference solution to the thermal diffusion differential, it is confirmed that: low short wave absorption helps to decrease the temperature difference in the date time between electric heating film and real target, while low infrared emission can decrease the temperature difference in the night. However, complete similarity of diurnal heat behavior between electric heating film and real target can not be reached only by material selection, so it is necessary to heat the electric heating film when its temperature is low.