PROBLEM TO BE SOLVED: To provide a device for producing hydrogen peroxide that can efficiently produce hydrogen peroxide using water and an oxygen-containing gas, and to provide an air conditioner, an air cleaner and a humidifier that use the hydrogen peroxide produced by the device for cleaning.SOLUTION: The device for producing hydrogen peroxide includes: an electrolytic cell 1 including an electrolyte membrane 2 having hydrogen ion conductivity, an anode electrode 3 disposed in contacting with a first surface of the electrolyte membrane 2 and a cathode electrode 4 disposed in contacting with a second surface of the electrolyte membrane 2； a power source 24 for applying a DC voltage to the anode electrode 3 and the cathode electrode 4； an electrolytic bath 7, a bottom surface of which is constituted of the electrolytic cell 1, and which stores water； a hydrogen peroxide collecting tank 22 provided below the cathode electrode 4； a gas feeding pipe 18 immersed into the water in the hydrogen peroxide collecting tank 22 to generate bubbles； and an oxygen-containing gas feeding device 17 for feeding the oxygen-containing gas to the gas feeding pipe 18, thereby efficiently producing hydrogen peroxide.【課題】水と酸素含有ガスを用いて過酸化水素を効率良く生成できる過酸化水素製造装置並びにそれにより製造された過酸化水素を洗浄に利用した空調機、空気清浄機及び加湿器を提供することを目的としている。【解決手段】水素イオン伝導性を有する電解質膜２と、電解質膜２の第１の面に接して配設された陽極電極３と、電解質膜２の第２の面に接して配設された陰極電極４とを備えた電解セル１と、陽極電極３と陰極電極４とに直流電圧を印加する電源２４と、電解セル１が底面の一部を構成して水を貯える電解槽７と、陰極電極４の下方に設置された過酸化水素回収槽２２と、過酸化水素回収槽２２内で水中に浸漬されて気泡を発生させるガス供給管１８と、ガス供給管１８に酸素含有ガスを供給する酸素含有ガス供給装置１７とを備えたもので、効率良く過酸化水素を生成できる。【選択図】 図６
