The invention relates to a waterproof and dustproof key, which comprises a PCB, a contact and a film, wherein a response region is positioned on the surface of the PCB, the film is provided with a flexible membrane layer, one end of the contact is adhered to the surface of the response region, the flexible membrane layer covers the other end of the contact, and the film is connected with the PCB in a sealed manner. By adopting the sealed connecting mode of the PCB, an adhesive layer and the film, a sealed region is formed inside the key, and the film is made of a waterproof easy-to-clean material, so that the key can be easily cleaned while resisting water and dust. In addition, an elastic sheet is arranged inside the key, so as to bring better hand feeling to the user, and obtain better sensory feedback on key pressing.