Abstract: This paper proposes a robust control algorithm for the trajectory tracking of robot manipulators with parametric uncertainty. The controller is designed based on a Lyapunov method , which consists of a nominal control part and a continuous state feedback compensator. It is shown that the effect of large parametric uncertainty can be eliminated and exponential stability can be guaranteed by using a continuous state feedback controller in the closed loop system for the robot manipulator. In addition, when the upper bound on the parametic uncertainty is assumed to be unknown, we modify the control scheme by introducing a simple estimation law in order that globally asymptotic stablity can be guaranteed.