Building steel structure multi-angle grinding device

The utility model provides a multi-angle polishing device for a building steel structure. The multi-angle polishing device comprises a bottom frame and a multi-angle polishing mechanism. According to the multi-angle grinding device for the building steel structure, the steel structure can be placed on a rotating rod and pushed forwards through rotation of a bearing, the grinding mechanism grinds the steel structure, and through arrangement of a first sliding block, a second stopping rotary knob, a second sliding block and a third stopping rotary knob in the multi-angle grinding mechanism, the steel structure can be ground conveniently; the distance between the first grinding wheel and the second grinding wheel can be adjusted by moving left and right in a sliding groove in the lifting column, the positions of the first sliding block and the second sliding block can be fixed through a second stop knob and a third stop knob, the first grinding wheel is transversely arranged and can grind the top surface of the