In sheet metal bending process, the system instruction following error and twocylinder synchronization error increase due to the difference and time variation of electrohydraulic proportional twocylinder model parameters and the interference of bending load. In order to reduce the negative influence of the errors on production efficiency and machine working condition, a compound control algorithm based on iterative feedforward and single neuron PID was proposed.The adaptive ability of single neuron PID was used to improve the robustness of the system against the bending load interference.Through iterative algorithm, feedforward control was learned to improve the system fast following, and the crosscoupling control was used to improve the twocylinder synchronization.The bending experimental results show that compared with the PID algorithm commonly used in engineering,using this compound control algorithm,the maximum tracking error and maximum synchro error are reduced from 2.1 mm and 0.14 mm to 0.5 mm and 0.055 mm respectively and the working condition of the machine tool is improved.The bending positioning cycle is shortened by about 18%, and the production efficiency is improved