Motor output setting means is provided which changes an output of a motor in accordance with a detection value of position detection means when a screen is driven in a downward direction. The motor output setting means changes the output of the motor in response to the screen reaching a first intermediate position and a second intermediate position between an uppermost position and a lowermost position of the screen. When the screen reaches the second intermediate position, the motor output setting means drives the motor by using a limited output obtained by adding a predetermined addable output to a minimum output for driving required for driving the screen in the downward direction. Such screen control device is aimed at optimization of motor output taking into consideration the catching (clamping) of foreign matter.