Abstract: This paper presents the research on high accuracy continuous path tracking control problem for robot ma-nipulators.First,it is shown that for a typical SISO variable structure control system,if the phaselag of theunmodeling part is over -π/2,then a boundary layer must be introduced,by using frequency domain analysis.The same analysis approach is extended to the general robot manipulators to determine the upper limit of thefeedback gain of controller,which plays an important role in achieving the high accuracy of the continuouspath tracking control.In the meantime,a simple and practical off-line dynamic parameter estimation approach is given.Finally,the result of continuous path tracking control with high accuracy is demonstratedthrough experiments.