Aiming at the disadvantages of traditional PI control such as poor dynamic and static control performance, a PI control method based on neural network was proposed. Combining neural network and traditional PI control, we constructed the neural network PI control system. Threelayer BP neural network was established, and through the gradient descent method the parameters were modified to achieve on line adjustment of k_p and k_i parameters. Through simulation and experimental verification, it was proved that compared with the traditional PI control method, the PI control system using neural network had faster response and smaller overshoot under different external conditions, which could significantly improve the dynamic and static performance of the system.