To solve design problems about precision of grinding manipulator system,manipulator kinematics parameter model based on DH method was built.A mathematical error model was built between kinematic parameters error and the endposition error by differentiation.Manipulator possible error sources were analyzed and summarized.This error sources were input into the error model to simulate effects of structural error and transmission error to manipulator endposition.The result shows that the transmission errors have greater impact on the X,Y position,and a greater impact on the Zaxis is appeared by structural error.The information can be used to the regression analysis for manipulators actual parameter error.At the design and manufacturing stages for the manipulator,the results can provide the referent data to the estimation and optimization for manufacturing and assembly errors of manipulator.