This paper introduces the concept of water mist technology, and discusses its extinguishment mechanism in comparison with other fire suppression systems briefly. Water mist has demonstrated some advantages in suppressing electrical and electronic fires (class C fires) .The electric characteristic of water mist, the variation law of breakdown strength to electrical equipment with water mist applied, the suspending and the smoke scrubbing ability of water mist are expatiated with a viea to the experimental results carried out by others. The investigation on efficiency and feasibility of water mist used in computer room and other electrical environment is thoroughly reviewed, and the working stability of electrical equipment with water mist applied is described. Effects of water mist diameter and velocity, water mist flux and barrier on water mist fire extinguishment efficiency are analyzed, and the application actuality of water mist in electrical environment is introduced.