Nowadays,the servo controllers used in the straighter in China are mostly simple PID control and their core processors are mostly MCU.Considering the limitations of MCU in poor data handling capacity,slow data operation and insufficient flexibility,it is difficult to satisfy the function requirements and accurate control of the straighter.Therefore,a high-accuracy straighter servo controller with the core of 32-bit floating point DSP-TMSF2812@150 MHz composed of BP-NN PID arithmetic was designed to apply to the servo control of the straighter.The experimental data show that this BP-NN PID servo controller has high control accuracy,good flexibility and timeliness.