A mask apparatus includes a mask body including an air duct disposed at a front surface of the mask body, and a fan module mounting portion disposed at a suction-side of the air duct, a fan module disposed at the fan module mounting portion and configured to supply external air to the air duct, a mask body cover that is coupled to the front surface of the mask body and covers the fan module and the air duct, a seal coupled to a rear surface of the mask body and configured to contact a user's face and define a breathing space for the user, a sealing bracket that fixes a portion of the seal to the rear surface of the mask body, and a pad configured to be disposed inside the breathing space.