According to an aspect, an illumination device includes a light source, a light adjustment device configured to control a light distribution angle of light emitted from the light source, and a controller configured to control the light adjustment device. The controller includes a storage configured to hold correspondence information indicating a correspondence relation between first data that is input from a control device and second data that is used to control the light distribution angle, a data generator configured to generate second data by adjusting the first data based on the correspondence information, and a driver configured to drive the light adjustment device based on the second data.