The invention relates to the technical field of building construction, in particular to a building protective fence. The building protective fence improves the anti-collision strength of the building protective fence, improves the convenient use effect of the building protective fence, reduces the occupied space of the building protective fence and improves the practicability. The building protective fence comprises square steel pipes, connecting plates, first rotating pins, a connection plate, a telescopic plate, a limiting bolt, screws, nuts, bases, moving mechanisms and connecting mechanisms, wherein cavities are formed in the square steel pipes, the multiple sets of connecting plates are rotationally connected through the multiple sets of first rotating pins, the connecting plates are rotationally connected with the square steel pipes, the telescopic plate is installed on the connection plate and slide relatively, a plurality of sets of limiting holes are formed in the telescopic plate, the limiting bolt is installed on the connection plate and connected with the limiting holes, the screws are fixedly installed on the square steel pipes, the connection plate and the telescopic plate are installed on the screws and rotate relatively, the nuts are installed on the screws in a screwed mode, the bases are fixedly installed at the bottom ends of the square steel pipes, and the moving mechanisms are installed on the bases.