The utility model relates to a can change blade holder of cutter automatically, including installing at base, the pull rod of installation on the object, drawing claw, uide pin and push rod, set up the inner chamber that the axial is the direction of height on the base, seted up the ring channel on the pull rod, draw the one end of claw to install in the ring channel, the pull rod can be followed the direction of height with an at least partially restrained who draws the claw and slided in the inner chamber, the partly of uide pin is connected with the pull rod, offer axial vertical in the slide hole of direction of height on the base, the push rod slides and sets up in slide hole, has offered the guide way on the push rod, and the center of guide way one end is higher than the center of its other end on the direction of height, another part of uide pin is passed the guide way and can be removed in the spout. The utility model discloses can realize need not to dismantle the function that the cutter can be changed to the blade holder, pure mechanical control, easy operation, safe and reliable both can automatic tool changing, also can manual tool changing, reduced and changed the required time of cutter, improved production efficiency.