To provide a lighting control system wherein a group number can be easily set for luminaires.

A plurality of the luminaires 16 are connected with the terminal device 12, the luminaires 16 are grouped and controlled with a terminal device 12 as a group. A setting machine 14 narrows down the luminaire 16 by turns according to lighting states of the luminaires connected with the terminal device 12 in setting the group number to the luminaires 16, eventually specifies the luminaire 16 to set the group number and set the group number to the luminaire 16.