The utility model provides a lightning-protecting simulative network disk circuit, which aims to solve the problem that a signal input line, a signal output line and a lightning protecting module R in the existing circuit are connected in parallel, wherein the signal input line is connected with the signal output line in parallel. When the device suffers lightning stroke, the output voltage is not only a residual voltage on the lightning protecting module, but the sum of the residual voltage on the lightning protecting module and the residual voltage of the two leads, which reduces the lightning-protecting effect of the device. The key points are as follows: the signal input line, the signal output line and the lightning protecting module are connected in parallel; and the signal output line is directly connected to two ends of the lightning protecting module. The active effect of the circuit is that when suffering lightning stroke, the circuit can greatly improve the protecting effect to the device.