To shield solar radiation by automatically driving a shading body such as a curtain to a shading position.

The automatic shading system includes: a plurality of solar radiation sensors 4a-4c arranged at different positions; a plurality of shading curtains 6a-6c arranged at different positions; driving motors 5a-5c individually driving the shading curtains between the solar radiation shading positions and the solar radiation not-shading positions; and a control body (programmable controller) 7 individually controlling the shading curtains between the solar radiation shading positions and the solar radiation not-shading positions by driving the driving motors based on sensor signals from the solar radiation sensors.