A wireless transmission system for transmitting a picture data between a transmitter and a receiver by wireless communication is provided. Each of the receiver and the transmitter is equipped with a directional antenna and a non-directional antenna. A communication of the picture data is performed by using the directional antennas, and a communication of a control data indicating a reception status of the picture data is performed by using the non-directional antennas. The transmitter controls an intensity of a signal radiated from the directional antenna of the transmitter based on the control data so that the intensity becomes a minimum intensity that can transmit the picture data.