A glue gun, wherein the glue gun comprises a movable handle and a fixed handle, and the movable handle is connected to the fixed handle via a pivot pin shaft; the movable handle is further provided with an actuating member, and the actuating member is provided with an actuating part cooperating with a push member; and a spacing between the pivot pin shaft and the actuating part is sized to be switchable between two or more gears, such that the magnitude of the force applied by the actuating member on the push member is changed; wherein the movable handle is provided with a sliding groove, which is provided with two or more gears; and the pivot pin shaft is arranged to be slidable in the sliding groove so as to enable switching between the gears; characterized in that: the pivot pin shaft is a stepped pin shaft having a pressing end, the pressing end is sheathed with an elastic component, the stepped pin shaft has a first shaft diameter portion and a second shaft diameter portion, the shaft diameter of the first shaft diameter portion is greater than the width of the sliding groove, the shaft diameter of the second shaft diameter portion is smaller than the width of the sliding groove, and the stepped pin shaft is arranged to: under the biasing action of the elastic component, the first shaft diameter portion is in the gear; when the pressing end is pressed down, the stepped pin shaft moves axially such that the second shaft diameter portion to goes into the gear; and when the pressing end is released, the stepped pin shaft moves axially in the opposite direction under the action of a restoring force of the elastic component such that the first shaft diameter portion goes into the gear again. the movable handle is further provided with an actuating member, and the actuating member is provided with an actuating part cooperating with a push member; and a spacing between the pivot pin shaft and the actuating part is sized to be switchable between two or more gears, such that the magnitude of the force applied by the actuating member on the push member is changed; wherein the movable handle is provided with a sliding groove, which is provided with two or more gears; and the pivot pin shaft is arranged to be slidable in the sliding groove so as to enable switching between the gears; characterized in that: the pivot pin shaft is a stepped pin shaft having a pressing end, the pressing end is sheathed with an elastic component, the stepped pin shaft has a first shaft diameter portion and a second shaft diameter portion, the shaft diameter of the first shaft diameter portion is greater than the width of the sliding groove, the shaft diameter of the second shaft diameter portion is smaller than the width of the sliding groove, and the stepped pin shaft is arranged to: under the biasing action of the elastic component, the first shaft diameter portion is in the gear; when the pressing end is pressed down, the stepped pin shaft moves axially such that the second shaft diameter portion to goes into the gear; and when the pressing end is released, the stepped pin shaft moves axially in the opposite direction under the action of a restoring force of the elastic component such that the first shaft diameter portion goes into the gear again.