Abstract: With the development of spatial infrared detectors towards large-surface array and long-line arrays,the low-temperature platform of the detector is difficult to be directly cooled by the cooler,and the traditional single-point thermal coupling mode cannot meet the temperature uniformity requirements of low-temperature arrays.For these prob-lems,a new bridge plate thermal coupling structure between large surface array detector and Stirling refrigerator is pro-posed,and the temperature distribution is simulated and analyzed by Workbench software,and verified by experiments.The results show that the temperature uniformity of the cold platform reaches 0.2 K,better than the design requirements.The rationality and feasibility of Stirling refrigerator and large array detector through bridge-plate coupling structure are proved as a reference for the subsequent development of thermal coupling technology of large array infrared detector.