Fine water mist can be used to restrain thermal hazard in some special situations, such as information center and telephone exchange center. A set of experiment was conducted to study the interaction of fine water mist with hot objects of different shape. An adjuster was designed to control the surface temperature of them avoiding over-heated. These objects were chosen to simulate the shape of cable and box used in electric equipment. Change of thermal field around these hot objects was measured before and after exertion of fine water mist. The flow procedure of fine water mist on the objects was displayed by an optical system. Vaporization height of fine water mist above different hot object was also measured. The restrain efficiency of fine water mist with different flux but same droplet size is compared. The experiment results serve as reference to engineering application of fine water mist to restrain thermal hazard of electric apparatus.