The invention relates to a 3D infrared temperature monitoring method and a system for a substation. The monitoring system comprises a bureau device data center, a substation device data center, thermal infrared imagers, high-accuracy holders and visible light cameras. The bureau device data center is connected with the substation device data center through networks, the substation device data center is connected with the thermal infrared imagers through a switcher by network cable interfaces, the substation device data center is connected with the high-accuracy holders through communication interfaces and connected with the visible light cameras through coaxial cables. The monitoring method comprises that infrared picture two-dimensional planar data obtained through the thermal infrared imagers are converted into 3D spatial data, 3D substation virtual scenes are generated through 3D modeling, and device models are subjected to corresponding body surface temperature color rendering. According to the 3D infrared temperature monitoring method and the system for the substation, thermal infrared imager temperature measurement is combined with substation 3D modeling, and accordingly, device temperature conditions can be displayed for 360 degrees in all directions and real time, and accuracy and effectiveness of monitoring are improved.