Abstract: An anti-slip structure of a respirator is provided. The respirator has a mask body whose top side is provided with a duct-connecting portion and whose lower end is peripherally provided with a closely fitting pad. In addition, the mask body has an outer surface provided with anti-slip portions, formed as concave recesses or raised patterns, on two opposite lateral sides of the mask body for being gripped by fingers. By pinching at the anti-slip portions on two opposite lateral sides of the mask body with fingers, an operator can handle the respirator easily and prevent the duct-connecting portion or the closely fitting pad from being tainted by bacteria on the fingers. Thus, not only can those parts of the respirator that are in direct or indirect contact with a patient remain in an uncontaminated and safe state, but also the operator can adjust the position of the respirator facilely.