A suspended ceiling converting support is arranged bellow nodes of an enclosure structure at the top of the building and connected with a sound absorption board, and comprises a main beam fixedly connected with the nodes of the enclosure structure at the top of the building, main keels and a subsidiary keel connected below the main beam; the main beam is enveloped by an anchor ear; a lifting lug is connected with the lower part of the anchor ear; the lower part of the anchor ear is connected with a hoisting ring at the upper part of a hoisting rod through a shackle; screw threads are formed at the lower part of the hoisting rod; the part with screw threads is inserted in a through hole formed on one of the main keels and screwed by a nut; the main keels have a grid-shaped structure connected in the horizontal direction; and the subsidiary keel is connected between the main keels. The system adopts non-welding method, thereby having the characteristics of convenient and fast installation and low construction cost; and the suspended ceiling converting support solves the construction problem that the sound absorption wall can not be directly connected with the enclosure structure. The suspended ceiling converting support can be widely applied to gymnasiums, odeums, conference centers, and other public constructions, which cannot be connected with the enclosure structure or have welding construction, particularly to a large-scale building with a membrane structure.