To provide an artificial breathing device by which timing of respiration can be seized easily as well as plural patients can be treated at the same time without touching their mouths directly.

This artificial breathing device is provided with a mask 1 by which mouth and nose of a patient is covered, an air supplying means 6 connected with this mask through an air supplying hose 3, a filter 4 which is provided on the air supplying hose 3, a respration changing-over means 5 by which air is supplied to the patients periodically via the mask by means of the air supplying means and also expired gas from the patient is released to outside, and a timing sound generating means 8 for generating a sound on the timing of respiration of the patient synchronously with the respiration changing-over means 5.