Applying the theory of kinematic accuracy and reliability, the research on reliability analysis of kinematic accuracy of label delivery mechanism, the key device of labeling machine, is carried out. Based on the geometric constraint equation of planar mechanism, the matrix method is used to derive the error expression of kinematic accuracy of plane mechanism, and the limit state equation for the failure of motion displacement accuracy and speed accuracy of label delivery mechanism (the linkage slider mechanism) of labeling machine is established, and the model of displacement and speed reliability of kinematics accuracy is constructed. Taking the machining error of the rod length into account, the reliability calculation of kinematic accuracy of the mechanism for labeling machine is realized by MATLAB computer program, the reliability of displacement and speed is obtained quickly and accurately, and verified by Monte Carlo method. The results show that the relative errors of this method are less than 0.5% compared with Monte Carlo method and this method is practical and effective.