The work aims to conduct the eye tracking experiment, so as to reduce the user??s cognitive load during the operation of interactive interface of digital instrumentation control system, and reduce the user??s error rate during the interactive operation of the digital instrumentation control system. The experiment uses the monitoring task interface of a nuclear power plant as a sample, and adopts the physiological response indexes of gaze and saccade to explore the information feature layout of the interactive interface of a digital instrumentation control system. Based on the analysis of the experimental data, error factors such as information omission, misreading/misjudgment occur in the visual cognition process of the interactive interface of the digital instrumentation control system. By extracting the error factors generated by the user in the operation process, a reference is provided for the design of the digital instrumentation control interface. The interactive interface design based on the error factors in the design cognitive process has certain reference value for reducing the error rate of tasks and improving the cognitive performance of the interface.