Abstract: The existing humidification device for air humidity and low temperature oxidation of coal basically adopts a single humidification method,which has low humidification accuracy,small humidification range and incomplete automatic humidification. In view of the above problems,based on the heat and humidity exchange principle,a mixing humidification method combining with water bath and high pressure atomization was proposed,and a mixing humidification experimental device of atomization and water bath was developed. The device realizes humidification by water bath and atomization step by step. The air enters the box through inlet pipe and contacts with water at the bottom of the device to realize water bath humidification. After the humidification of water bath,the air comes out from the water and continues to contact with the water mist in the box after high-pressure atomization,thus realizing high-pressure atomization and humidification. The air outlet of the device is equipped with a humidity controller,which can set different relative humidity according to the needs,and can detect the air in the device in real-time,so as to achieve accurate control of air humidification. The mixing humidification method of water bath and high pressure atomization not only shortens the humidification time of the air,but also enlarges the humidity regulation range of the device,so as to realize the humidification needs of different ranges.