Provided is a sulfide gas concentration measurement device that comprises: an exhaled-air collector that is fitted to a subject and into which air exhaled by the subject is introduced; a pressure regulator that is equipped with an entrance port to which the exhaled-air collector is connected; a sulfide gas sensor that is connected to an exit port of the pressure regulator and measures the concentration of sulfide gas in the exhaled-air output from the exit port; and a pressure gauge. The pressure gauge is configured to measure the pressure at the entrance port of the pressure regulator and to present the measured pressure to the subject.