Abstract: For different types of ice accretion on the airfoil surface under different icing conditions, numerical method is used to study the ice density effect on the heat conduction and the ice melting process during electrothermal de-icing process. A standard three-dimensional electrothermal de-icing model, which is covered with different ice on the airfoil metal surface, is applied in the numerical simulation. The temperature at several points in the simulated model is monitored, and the interface between the airfoil metal surface and the ice is set as the monitoring surface. The temperature variations are recorded at these monitored points and surfaces during the simulation of electrothermal de-icing process. These temperature characteristics can be used to analyze the effect of the ice density on the ice melting. Three kinds of ice with different densities are selected as the research objects. The temperature variations of rime ice during the melting process are compared with glaze ice. The results indicate that the ice density has significant effect on the electrothermal de-icing process. When the ice density decreases, the speed of the ice temperature rising increases, together with early initial time for the ice melting, and the whole melting process is shortened.