Abstract: This paper describes a graphic simulation system of trajectory planning of robot,manipulators on IBM-PC.This system can be to analyze kinematics and optimum trajectory planning of robots.A three dimensional geometrie model of a manipulator and its envirinment consistion of generalized,bodies can begenerated.The system simulates under interactive code.The movement of link of manipulator has dynamiceffect on CRT of a microcomputer.Based on the MINIMAX principle,we present dynamic performanccindex for trajectory planning.Path planning carried out by this index will be made into minimum.joint driving torques.At last,simulation results of a PUMA 560 manipulator are given.