The invention discloses a steel frame for building renovation with good protection performance, which comprises a bracket, and a plurality of square spaces are formed on the bracket, and each square space includes a square frame arranged at an edge position, and the outside of the square frame is connected with a side The side bars are fixedly connected with each other to form a square side frame, and the four corners of the square frame are provided with fan-shaped guardrail components. The connecting shaft is arranged between the square frame and the side rod, the positioning rod is rotatably connected with a transition rod, the transition rod on the adjacent positioning rod is connected through the connecting rod, the transition rod and the connecting rod are rotatably connected, and the The transition rod is set at the same length as the connecting rod, the transition rod is shorter than the positioning rod, and the ends of the connecting rods arranged at both ends of the guardrail assembly are provided with positioning pieces for fixed connection with the square frame. The protection effect is better, and at the same time, it is easy to install and has a better use effect.