The utility model relates to a connection piece of a ring network cabinet frame, which is used for detachably connecting two frame horizontal beams and a pillar. The connection piece is characterized in that: the connection piece comprises an 'L' shaped bottom seat formed by two mutually vertically connected rectangular horizontal branched pipes and a vertical sleeve vertically connected with the bottom seat on the connection position of the two branched pipes. When a ring network cabinet is mounted, two branched pipes of the bottom seat are detachably fixed and connected with the frame horizontal beam the sleeve is detachably fixed and connected with the pillar, a fixation connection is added on the pillar and the frame of the ring network cabinet, thus the whole ring network cabinet is disassembled and assembled in place and the parts such as the damaged pillars, panels or frames are conveniently exchanged. The connection piece has the following beneficial effects: 1, the maintenance cost is low, the whole cabinet is not needed to be exchanged, a cable head is not needed to be produced again and compared with the prior technology the exchange cost is reduced by about 20 times; 2, the order time of the products is short and generally the exchange time only needed about 2 days; 3, the power failure operation is not needed and no adverse effect is brought to the society and the user.