To provide a system to facilitate the mounting of an electric switch which automatically turns on light without operating an illumination switch when a person enters a widely common house front door, a hotel room entrance part, a living room, bathroom, a lavatory, etc., and turns off the light by confirming that the person has left after a certain time elapsed.

This system includes a battery-operated detection part 1 that is easy to install and has a detection circuit to sense the presence or absence of a person and a remote control function, and an illumination switch part 2 having a built-in receiving part, and can easily realize an automatic illumination turning on-off system obviating the need of a large-scale electric wiring construction. Thereby, it is safe because luminaire switch operation in the dark is eliminated and energy saving is also realized by preventing the turning-off of the illumination from being forgot.