Abstract: When infrared equipment is used for operation and maintenance diagnosis in power transmission and transformation systems, it is required that the ambient temperature be greater than 0 ℃. However, there is a lack of infrared diagnostic basis for live equipment in low-temperature winter environments in Northeast China. Therefore, it is necessary to study the relationship between the metal contact point temperature of typical electrical equipment/connectors and the ambient temperature. This paper builds a low-temperature infrared testing system in a laboratory environment, obtains the variation law of metal contact point temperature of the equipment at different environmental temperatures, and reveals the influences of three contact resistances on the testing temperature under different load currents and environmental temperatures. The test results indicate that, when the contact resistance is less than 20 μΩ, the environmental temperature and load current have hardly any effect on the temperature gradient of the contact point. And when the contact resistance is greater than 20 μΩ, the influence of load current significantly increases, and 0 ℃ can serve as the boundary point for temperature gradient changes. Thereby, a correction method for low-temperature infrared temperature measurement is proposed after considering contact resistance, which can correct the influence of low-temperature environment on infrared temperature measurement results. The analysis and experimental results in this paper provide a practical basis for correcting infrared detection results in low-temperature environments. The research results of this paper can accurately determine problems such as abnormal contact of electrical equipment, and provide important theoretical support for the formulation of maintenance strategies for electrical equipment in alpine region.