For assessing dispersiveness ofmeasuring result of positional distance accuracy (ADp) of industrial robot, based on the research on the measuring principle of the Laser Tracker and the measuring method of ADp for industrial robot, some work was done for analyzing uncertain factors and their influence on the measuring result of ADp of industrial robot, and then a comprehensive method for assessing the uncertainty of ADp was developed. The results show that the method is reliable. Evaluation result provides the basis for assessing local precision of Laser Tracker, contrasting precision of different instruments, and analyzing the influence of some uncertain factors (such as environmental change and personnel operation) on measuring resultes, and it is beneficial for improving comprehensive accuracy of measurement.