Abstract: A caulking gun includes a push disk, a push rod, an adhesive cartridge compartment, a trigger and a gun body; the trigger is hingedly coupled to the middle part of the gun body; the rear end of the push rod is outside the gun body and provided with a braking device; the front end is in the adhesive cartridge compartment through the gun body and provided with a push disk; a push piece for driving the push rod is mounted in the gun body; the front end of the push piece is provided with a return spring; the trigger is provided with a pin position switching device for adjusting the propulsion ratio by adjusting the contact position of the push piece; adjustment of different propulsion ratios enables the caulking gun to be multifunctional to meet the construction requirements of different adhesives.