In view of the relevent experiments and tests on the industrial robot spring balance cylinder, the change of its paraments has a big impact on the unbalanced moment of industrial robot. In order to improve the working performance and efficiency of industrial robots, the influence of parameters on the unbalanced moment balance cylinder was analyzed and optimized. Based on researching and testing the gravity parameters and structure parameters of the industrial robot, the unbalanced moment of industrial robots was deduced. It was obtained that the various parameters were exercised of a great influence on the unbalanced moment, as well as kinematics and dynamics characteristics of the robot. By structuring parameters of related constraint condition and the objective function of nonlinear constraints, the engineering example was optimized by combined the multiple objective function optimization model. Lastly, the results before and after optimization were analyzed in comparing to obtain related optimal effects. The experimental results show that the optimization results meet the experimental requirements. After optimization, the maximum unbalanced moment is reduced, and the robot movement is more stable. The optimizing system has the effectiveness and practicability.