An atomizing device of an electronic cigarette, comprising a main body, a heating device and a waterproof and breathable membrane, wherein the main body is provided with an air inlet, a suction port and an oil storage chamber, the main body forms an airflow channel between the air inlet and the suction port, the heating device is partially received in the airflow channel and is communicated with the oil storage chamber, the waterproof and breathable membrane is installed on the main body, and the waterproof and breathable membrane covers the airflow channel between the air inlet and the heating device; characterized in that: the waterproof and breathable membrane comprises a base material with waterproof and breathable properties and an anti-wrinkle ring, the anti-wrinkle ring covers the edge of the base material so that when the base material is installed on the main body, the part of the base material not covered by the anti-wrinkle ring covers the airflow channel and forms a breathable part, and the breathable part is communicated with the airflow channel through an air path; the main body comprises a base body and a chassis; the air inlet is provided on the chassis, the airflow channel forms an air passage hole communicated with the air inlet on the outer surface of the chassis, the chassis is further provided with an installing groove on the periphery of the air passage hole, the waterproof breathable membrane is installed in the installing groove, and the breathable part of the waterproof breathable membrane covers the air passage hole so that the breathable part is communicated with the air passage hole through an air path; and the suction port, the oil storage chamber and the heating device are received in the base body, when the base body is installed on the chassis, the base body covers the installing groove, and the heating device is communicated with the breathable part of the waterproof and breathable membrane. the waterproof and breathable membrane comprises a base material with waterproof and breathable properties and an anti-wrinkle ring, the anti-wrinkle ring covers the edge of the base material so that when the base material is installed on the main body, the part of the base material not covered by the anti-wrinkle ring covers the airflow channel and forms a breathable part, and the breathable part is communicated with the airflow channel through an air path; the main body comprises a base body and a chassis; the air inlet is provided on the chassis, the airflow channel forms an air passage hole communicated with the air inlet on the outer surface of the chassis, the chassis is further provided with an installing groove on the periphery of the air passage hole, the waterproof breathable membrane is installed in the installing groove, and the breathable part of the waterproof breathable membrane covers the air passage hole so that the breathable part is communicated with the air passage hole through an air path; and the suction port, the oil storage chamber and the heating device are received in the base body, when the base body is installed on the chassis, the base body covers the installing groove, and the heating device is communicated with the breathable part of the waterproof and breathable membrane.