The utility model discloses dehumidification anti -condensation device that looped netowrk cabinet is unpowered belongs to dehydrating unit technical field, the technical problem that will solve is area looped netowrk cabinet condensation autumn and winter in the north, the technical scheme who adopts does: relative two the side lower parts of looped netowrk cabinet are respectively through the first ventilation pipe and second ventilation pipe intercommunication of pipeline with L shape, and wherein pass through three way connection and two elbows link to each other at the top of first ventilation pipe, but the top of second ventilation pipe is continuous through the unpowered updraft ventilator that thrust bearing and horizontal rotary drum moved, it is hollow globular that unpowered updraft ventilator is the bottom open -ended, has a plurality of ARC blade on the spheroid, misplaces between the adjacent blade and have the space, vertical decurrent nozzle stub is connected on the horizontal pipeline of second ventilation pipe, and blind nut among the automatic water discharging device passes through threaded connection on the nozzle stub, and the drainage chamber is for fixing the inversion arc tip cavity on the blind nut, and tip department opens has the delivery port, the utility model discloses the formation of northern area condensation autumn and winter has been prevented.