The utility model provides a C-shaped steel purline structure reinforced by an angle brace, which relates to the technical field of angle brace reinforced C-shaped steel purline structures, and comprises a mounting frame and a main body, the side surface of the main body is fixedly provided with a fixing frame, the side surface of the mounting frame is fixedly provided with a rotating block, and the side surface of the rotating block is rotatably connected with a mounting block. A mounting rod is fixedly mounted on the surface of the mounting block, a sliding rod is slidably connected to the surface of the mounting rod, and according to the design of the sliding rod and the positioning plate, mounting is more flexible, adjustment can be conducted according to actual conditions, and different construction requirements can be met. Meanwhile, due to the threaded connection and anti-skid thread design of the lead screw and the positioning plate, the accuracy and safety in the adjusting process are enhanced, the loosening problem in the mounting process is avoided, and the mounting convenience is improved.