To effectively inhibit the fluctuations of the manipulator speed movement, an algorithm based on non-uniform rational B-splines (NURBS) curve for the trajectory planning of 7-DOF redundant manipulator was proposed. Depending on the nature of NURBS, make the points on motion path of the joint as the curve control points, calculate the non-uniform knot vector based on the absolute motion distance, regard the weight factor as one of the constrained variable to control the speed and acceleration, make the trajectory of the manipulator with a high accuracy approximation of predefined trajectory. This planning was obtained by establishing coordinate system and creating kinematic model through geometrical analysis, and also using computer to simulate the planning trajectory. The experiment result shows that the effectiveness and feasibility of the proposed trajectory planning of redundant manipulator based on NRUBS are verified.