Protective film, circuit board assembly and preparation method thereof, and display module

The invention provides a protective film, a circuit board assembly, a preparation method of the circuit board assembly and a display module. The protective film comprises a first insulating layer, a conductive layer and a second insulating layer, wherein the first insulating layer, the conductive layer and the second insulating layer are sequentially stacked in the thickness direction of the protective film; the airflow channel is arranged on the protective film and comprises a first opening, a second opening and a third opening, the first opening is formed in the first insulating layer, the second opening is formed in the conductive layer, the third opening is formed in the second insulating layer, and the first opening, the second opening and the third opening are sequentially communicated to form the airflow channel. According to the protective film, air between the protective film and the side wall face of the electronic component can be exhausted through the first opening, the second opening and the thir