Abstract: A face mask for medical use, respiration anesthesia or first aid use. The face mask is structured from a main body casing made of hard plastic, with a tubular shaped air inlet protruding from the surface of casing; and a mouth-shaped adhering piece made of soft elastic plastic. The adhering piece is formed on the peripheral edge of the opening of casing, and is used to adhere to the user's face. Anti-slip portions that are formed as an integral body with the soft adhering piece and formed as protruding strips, sheet forms, protruding points or a mixed configuration thereof are provided on at least one portion of the surface of casing. The anti-slip portions are used to enable health care personnel to easily hold the face mask and prevent the face mask from slipping when fitting it to a patient or removing from the patient for cleaning and sterilizing.