In order to precisely evaluate the workload of air traffic controllers,quantitative analyses of effective fac-tors are significant.Considering the traffic situation in sectors as well as the performances of controllers,14 key factors are identified in the analysis of controllers′ workload,the weights of which are computed by grey correlation entropy. Then an analysis on the workload of air traffic controllers is conducted,and the magnitude of its identification coefficient is optimized.The data collected from a radar simulator of 01/19 area in a control sector of Beijing are applied for model validation.It indicates that the number of ground-air communication,times of equipment operation,and sector access in-dex are the most important factors influencing the workload of controllers.The weighted gray correlation degree of these three factors are 0.844 0,0.796 1,and 0.693 5 respectively.Moreover,the ranking results of weighted gray correlation degree are consistent with the controllers′subjective ranking results by Analytic Hierarchy Process (AHP)method.The relative importance of influencing factors on air traffic controllers′workload can be revealed by the weighted gray correla-tion degree analysis.