Climate room is an important instrument to study the icing problems in power networks, and the accuracy of the data from the climate room is under debate. There are many climate rooms in the world, but no standards about the parameters of the climate room such as the room＇s temperature, the velocity of the wind, and the particle diameters of the water droplets etc. These parameters will influence the icing processes on the lines and insulators. This paper gave a summary of the process and the feature of atmospheric icing of power networks. The speed of the icing on a cylinder rod as a new characteristic quantity was proposed to study the de-icing problems in this paper. For the purpose to analyze the equivalence between atmospheric icing and icing in climate room, a finite element model was made based on a small climate room located in the Graduate School at Shenzhen, Tsinghua University. Through the simulation analysis for the heat transfer and flow issues, the result showed that precooling droplets were cooled into supercooled ones soon after they came into the climate room. Based on the most serious icing-speed in Hengshan, Hunan and a series of experiments, the values of some parameters in studying icing problems were proposed to better simulate the atmospheric icing in climate room.