The utility model provides a cubical switchboard temperature -detecting device based on cabinet door external measurement, includes wireless temperature measure module, intelligent control module, keying input module, display module, power module, USB data communication module. Wireless temperature measure module includes infrared thermopile inductor, signal processing chip, wireless temperature measure module links to each other with power module and intelligent control module, and wireless temperature measure module is used for issuing the intelligent control module with the temperature information that detects. Keying input module includes the oval button of two buttons, is used for the input volume of opening dynamic testing signal respectively, shows switching signal, keying input module links to each other with the intelligent control module. USB data communication module includes integrated general USB interface, and it provides data reading and writing people having a common goal for external device, and USB data communication module links to each other with the intelligent control module. The utility model discloses the device utilizes the temperature field analysis of cubical switchboard, establishs the relation between the high temperature electricity in cabinet door point for measuring temperature and the cabinet in advance, through measuring switch cabinet doors outer surface temperature, obtains the temperature at required temperature measurement position in the cabinet indirectly. Overcomes the deficiencies in the prior art, the temperature measurement is accurate convenient, has more the practicality.