A breathing mask, capable of connecting a gas generator for providing gas generated by the gas generator to a user, includes a main body, a gas inputting tube, a one-way valve, and at least one gas exiting tube, wherein the main body further includes a containing part which forms a containing space for containing the nose of the user. The gas inputting tube is connected to the gas generator for providing the gas to the containing space. The one-way valve allows the gas to pass from the gas input tube to the containing space but blocks the gas from the containing space to the gas input tube. The gas exiting tube enables the gas to exit out from the containing space. The user can breathe in the gas generated by the gas generator from the containing space, and the waste air can exit through the gas exiting tube.
