Abstract: A trajectory simulation planning system based on Vega for dual-arm space robot to capture an object is presented.The development environment and realization method of the simulation system are introduced briefly.This simulation system runs on SGI workstation,and makes use of Multigen Creator modeling tool and the three-dimension vision simulation software Vega to realize the modeling and simulation of the robot body and the captured target.This simulation system can provide important information for robot trajectory planning,kinematics analysis and motion control algorithm design,and can be used to validate the feasibility of theory and algorithms.