Abstract: A lighting-emitting diode (LED) lamp string device with a battery box is provided. The LED lamp string device includes a power supply system and a lamp string light emission system connected together. The lamp string light emission system includes an LED lamp string that is composed of a plurality of LED lamps and electrical wires that electrically connect the LED lamps. The power supply system includes batteries and a light controller that are connected to the LED lamp string through the electrical wires and further includes a battery box, in which the light controller and the batteries are received.