A lighting system comprising an indoor lighting device installed at a first space, a mobile terminal and a wireless communication network, the indoor lighting device comprising: a light emitting unit; a storage unit adapted to store a conditional table including information of an operating condition of the light emitting unit according to an operating state of the mobile terminal; a wireless communication unit adapted to receive an information of an operating state transmitted from the mobile terminal through the wireless communication network; and a controller installed at said first space and adapted to determine if the mobile terminal is located at said first space, wherein if said mobile terminal is determined as being located at said first place, said controller is further adapted to receive the information of the operating state of the mobile terminal through the wireless communication unit, to decide an operating condition of the light emitting unit corresponding to the received information of the operating state, based on the stored conditional table and to operate the light emitting unit based on the decided operating condition), characterized in that the information of the operating state of the mobile terminal comprises a charge state of a battery provided in the mobile terminal, wherein the controller is adapted to decide the operating condition of the light emitting unit based on an information of a residual amount of the battery received through the wireless communication unit; wherein the operating condition of the light emitting unit comprises a power condition and a brightness level condition, wherein the brightness level of the light emitting unit depends on the residual amount of the battery, wherein if the residual amount of the battery is 100%, the controller is adapted to supply operating power to the light emitting unit while controlling the light emitting unit to emit light with 100% of brightness, wherein if the residual amount of the battery is 0%, the controller is adapted to cut off the operating power supplied to the light emitting unit, and wherein if the residual amount of the battery is more than 0% and less than 100%, the controller is adapted to supply operating power to the light emitting unit while controlling the light emitting unit to emit light with a corresponding level of brightness. a light emitting unit; a storage unit adapted to store a conditional table including information of an operating condition of the light emitting unit according to an operating state of the mobile terminal; a wireless communication unit adapted to receive an information of an operating state transmitted from the mobile terminal through the wireless communication network; and a controller installed at said first space and adapted to determine if the mobile terminal is located at said first space, wherein if said mobile terminal is determined as being located at said first place, said controller is further adapted to receive the information of the operating state of the mobile terminal through the wireless communication unit, to decide an operating condition of the light emitting unit corresponding to the received information of the operating state, based on the stored conditional table and to operate the light emitting unit based on the decided operating condition), characterized in that the information of the operating state of the mobile terminal comprises a charge state of a battery provided in the mobile terminal, wherein the controller is adapted to decide the operating condition of the light emitting unit based on an information of a residual amount of the battery received through the wireless communication unit; wherein the operating condition of the light emitting unit comprises a power condition and a brightness level condition, wherein the brightness level of the light emitting unit depends on the residual amount of the battery, wherein if the residual amount of the battery is 100%, the controller is adapted to supply operating power to the light emitting unit while controlling the light emitting unit to emit light with 100% of brightness, wherein if the residual amount of the battery is 0%, the controller is adapted to cut off the operating power supplied to the light emitting unit, and wherein if the residual amount of the battery is more than 0% and less than 100%, the controller is adapted to supply operating power to the light emitting unit while controlling the light emitting unit to emit light with a corresponding level of brightness.