In this paper, the authors investigated direct heat exchange between snow and air. Hot air is cooled directly on the surface of snow through a vertical hole dug into a snow pile. Temperature changes of cooled air and shape changes of snow were observed by means of an experiment apparatus with the size of actual equipment. By reference to the actual conditions of an air-cooling system, initial snow height of snow pile, inlet air temperature and air flow rate were changed as parameters. The outlet air temperatures and snow shapes were measured. The following results were obtained. When the amount of remaining snow is decreased, the diameter of snow hole increases lineally and the snow height decreases lineally. The initial snow height is higher, air flow rate is larger and inlet air temperature is lower, the outlet air temperature becomes lower. And the authors derived an experimental equation to describe the relationships between the outlet air temperature and every parameter.