The invention discloses a fireproof air breathing device which comprises an air respirator steel cylinder. The top and the bottom of the air respirator steel cylinder are each connected with a cover body, wherein the cover body located on the top of the air respirator steel cylinder is rotationally connected to the air respirator steel cylinder, the cover body located on the bottom of the air respirator steel cylinder is fixedly connected with the air respirator steel cylinder, a connecting pipe is arranged on the cover body located on the bottom, the top of the connecting pipe penetrates through the cover body to be communicated with the air respirator steel cylinder, a pipe valve is installed at the position, close to the air respirator steel cylinder, of the connecting pipe, the connecting pipe adopts a hard pipe body, and a respirator mask is arranged at the end, opposite to the air respirator steel cylinder, of the connecting pipe. The fireproof air breathing device is reasonable in structural design, has the functions of a respirator and the pneumohydraulic function, the fireproof air breathing device can be better utilized, the using safety and protectiveness are enhanced, and the defects that during fire rescue, an existing breathing device is short in using time, gas supplementing is difficult, the existing breathing device is easy to damage, and convenience and practicability are poor can be overcome.