Plug lock

The invention relates to a plug lock which comprises an external lock body, an intermediate core body, two or more plugs, springs and a key. The internal wall of the lock body is provided with two or more circumferential concave grooves and one or more axial concave groove; one or more axial keyhole and an opening groove which is communicated with the axial concave groove of the lock body are formed in the core body; the two or more plugs are mounted in the keyhole in a stacking manner, tails of the plugs are latched in the opening groove of the core body and the axial concave groove of the lock body, and the compression springs are mounted between the plugs and between the plugs and the bottom of the keyhole; the heads of the plugs are provided with through holes, the sizes of the hole diameters of the through holes of all the plugs are unequal, the plug with the smallest hole diameter is mounted inside, and the plug with the largest hole diameter is mounted outside; and the key is of a tapered rod with a sm