The invention discloses a dehumidification and anti-condensation intelligent control system and method for a ring main unit. The system is based on the thermoelectric refrigeration technology and the wireless sensor network technology, a fuzzy fractional order PID controller is adopted, the temperature and the humidity of the working environment are monitored in real time, and intelligent control dehumidification is achieved. In combination with a wireless sensor network platform with the complete function, a user can achieve the purposes of holding a device for polling in a field and remotely and online monitoring the state of equipment in real time. The condensation dehumidification device can effectively reduce the humidity of space air, the condensation phenomenon is avoided, and the condensation dehumidification device has the advantages of being small in size, low in operation cost, long in service life and high in reliability, and is widely applied to dehumidifying various closed cabinets such as a switch cabinet, a power distribution cabinet and a terminal box.