The measuring device 1 includes a measurement vessel 13 contained a liquid 12 filled therein, and a sensor 11 provided in the measuring vessel 13 and for detecting components of a gaseous sample dissolved in the liquid 12. The measuring device 1 also includes a bubble-generating unit 14, which is supplied with a gaseous sample and has an aperture 141 for discharging the gaseous sample in form of bubbles into the liquid. The aperture 141 faces the sensor 11 and the bubble-generating unit 14 is disposed to have a predetermined clearance with the sensor 11. A relation of 1/2Y≦X≦3/2Y is satisfied, where X represents a distance of a clearance between the bubble-generating unit 14 and the sensor 11 and Y represents a diameter of the aperture 141 of the bubble-generating unit 14.