A control strategy for machining contour error was proposed for robotic machining complex surface parts.The contour error of the robot processing task was defined in the form of vector,and the robot contour error was estimated by combining bidirectional search,Fibonacci search and spherical linear interpolation algorithms.On this basis,the contour control strategy of the robot processing task was designed by compensating the weighted contour error component to the speed command in the robot task space.The experimental results show that the difference between the estimated value and the true value is very small for the position and attitude contour errors,and the average error of the position and direction contour is reduced about 30% compared with the simple tracking control,which verifies the effectiveness of the proposed processing contour error control strategy.