Mounting structure of chair backrest

The utility model relates to a mounting structure of a chair backrest. The mounting structure of the chair backrest comprises a back frame of the chair backrest and steel racks of a chair back leg, wherein semicircular slots matched with the steel racks of the chair back leg are arranged on the outer side faces of the left and right sides of the back frame; through holes are formed in the bottoms of the semicircular slots, mounting holes are arranged on parts, corresponding to the through holes, of the inner sides of the steel racks of the chair back leg, the upper ends of the steel racks of the chair back leg are inserted into the semicircular slots, and screws penetrate through the through holes from the inner side of the back frame of the backrest and are in threaded connection with the mounting holes. The mounting structure of the chair backrest has the advantages that the structure is simple, the cost is low, and the mounted screws are hidden, so that the overall appearance of the chair is not influenced; besides, the chair backrest can be fixed by only two screws, so that materials are saved.