Due to the large workspace， flexible posture， high configurability and low cost， industrial robots are widely used in various fields such as transportation， assembly， spraying， welding， etc. Because of the low precision of robot end track and the large fluctuation at low speed， it is rarely used in the field of electrochemical machining. According to the characteristics of low speed and high trajectory accuracy of electrochemical machining， a quadrant method is proposed to set the working area of the electrochemical machining robot and the dynamic optimization function of the electrochemical machining robot is establisbed. The third-generation non-dominated genetic algorithm NSGA-Ⅲ is used to solve the optimal Pareto solution set of each design parameter. The dynamic performance test is carried out through simulation and experiment. The results show that within the set working area， the straight track accuracy of the electrochemical machining robot can reach 0.073 mm， the arc trajectory accuracy can reach 0.145 mm， and the trajectory accuracy under low-speed conditions is nearly 10 times higher than that of traditional industrial robots.