A cutting-power-off detection structure of a toy gun has a main structure that includes a gun body, a muzzle defined at one side of the gun body, a feeding channel defined in the gun body, a chamber defined in the gun body and in communication with the muzzle and the feeding channel, a circuit device arranged in the gun body, at least one wireless detection device arranged in the gun body and electrically connected with the circuit device, and a shot forwarding device arranged in the chamber and electrically connected with the circuit device. The feeding channel is connectable to a magazine and the wireless detection device is operable to detect a shot fed from the magazine. When the magazine runs out of shots and the wireless detection device detects no shot, a signal is transmitted to the circuit device to cut off electricity supplied to the shot forwarding device.