An IEEE 1394 device detecting circuit includes a south bridge chip, a control device, an IEEE 1394 interface, and a resistor. The control device includes a power reset pin, a bus reset pin, and a cable power pin. The control device is connected to the south bridge chip through the bus reset pin, which is further connected to the power reset pin. The cable power pin is connected to a direct current power through the resistor. The control device is further connected to the IEEE 1394 interface, which is connected to an IEEE 1394 device.