Abstract: In this paper, the operator simulator retraining in a certain nuclear power plant with a digital control room is to be carried out a field observation, in order to collect image data of operating behavior and response time in the digital operating platform. According to the applied behavior analysis technology of image data, the various operating behaviors are grouped to obtain the mean of response time. The operation mode for digital operating platform and the response time of each operating action group are finally determined. The research results provide a strong theoretical and practical basis for defining the qualitative description of human reliability analysis and reducing the uncertainty of quantitative analysis.