The utility model provides a novel omnipotent knee type milling machine based on activity guard shield structure, including base, main shaft fixed plate, main shaft, guide rail, transmission case, activity guard shield, fixture device, adjust knob and control box, the main shaft fixed plate fix the rear portion position at the base, the main shaft fix the upper portion at the main shaft fixed plate, the guide rail setting on the upper portion of main shaft fixed plate, the transmission case setting on the upper portion of base, movable guard shield setting in the left side of workstation, fixture device set up the right side at the activity guard shield, the utility model discloses a flexible shell, fixed orifices, fixed plate, compress tightly the setting of pole and rotary rod, be favorable to better guide rail to avoid the injury that iron fillings brought, increase of service life, movable guard shield is placed to better cooperation guide rail, less area is required, reinforcing apparatus's stability makes its guarantee the machining precision, utilizes the rotary rod to make things convenient for the installation and the dismantlement of anchor clamps.