The invention discloses a dry-type air reactor overheating fault detection method, device, and system. The method comprises steps of: presetting temperature-measuring points over the air channel port of a dry-type air reactor and in the environment around the dry-type air reactor so as to directly acquire the temperature of the temperature-measuring point over the air channel of the dry-type air reactor in a running state and the temperature of the temperature-measuring point in the environment when fault detection is performed; computing the temperature rise of the air channel port of the dry-type air reactor by means of the two temperatures; and determining that the dry-type air reactor is subjected to a overheating fault when the detected temperature rise is over a preset temperature rise threshold. The method prevents manual field temperature acquisition, acquires the temperature by means of the preset temperature-measuring points, processes a temperature signal by means of a processor, may detect whether the dry-type air reactor is subjected to the overheating fault, and greatly facilitates operation and maintenance while reducing operation and maintenance cost.