To provide an electric blind capable of improving the efficiency of cooling and heating in an indoor side in summer and winter.

In this electric blind, heat shut-off paint is applied on a surface of slat, and heat insulation paint is applied on a rear surface of the slat. A control circuit 3 incorporates a radio wave clock, determines four seasons from the information of date based on standard radio waves received by the radio wave clock, and calculates an angle of incidence of the sunlight changing every moment from the information of latitude and longitude input from a remote controller 4. In summer, the control circuit outputs control signals to let an angle of the slat of the blind 1 cross the angle of incidence of the sunlight orthogonally. In winter, the control circuit outputs control signals for controlling the angle of the slat at which the sunlight reflected on the surface of the slat 3 is applied on the rear surface of the slat 3. In spring and fall, this electric blind switches automatically to switch the angle of the slat by manual operation through a remote control device 6.