The invention discloses a buckle screwing and unscrewing device for an iron roughneck. The buckle screwing and unscrewing device comprises clamping pliers, buckle punching pliers, and a buckle punching oil cylinder, wherein one end of the buckle punching oil cylinder is fixed on the clamping pliers, and the other end of the buckle punching oil cylinder is hinged to the buckle punching pliers; a supercharging device is connected to the buckle punching oil cylinder, and under at least one predetermined state, a rod cavity of the buckle punching oil cylinder is used for oil intake, and a rodless cavity is used for oil returning; the supercharging device provides pressure Pa which is larger than the system pressure P for the rod cavity of the buckle punching oil cylinder. According to the buckle screwing and unscrewing device disclosed by the invention, the supercharging device is additionally arranged, so that the working pressure of the buckle punching oil cylinder is increased; in addition, under the condition that the system of a whole pumping station is maintained unchanged, and the external dimension, the structure and the mounting dimension of the buckle punching oil cylinder are maintained unchanged, no matter whether a drilling tool is screwed forwards or backwards, the buckle screwing torque and the buckle unscrewing torque which conform to design requirements can be achieved. The invention further discloses the iron roughneck and petroleum drilling equipment.