The work aims to design a die-cutting mechanism for roll-to-roll film automatic melting and assembling zipper equipment to achieve the function of dotted die-cutting lines on the film. A die-cutting mechanism composed of an eccentric shaft slider mechanism and a movable cutter mechanism was designed and driven by servo motors. A dynamic model of the mechanism was established. The particle swarm algorithm was used to optimize the mechanism parameters to reduce the inertial force of the reciprocating motion of the mechanism, thereby reducing the vibration caused by the inertial force and the difficulty of controlling by servo motor. The die-cutting mechanism was optimized in Adams, and a damping device to flexibly connect the slider and the cutter mechanism was designed to further optimize the damping performance of the die-cutting mechanism. The inertial force of the mechanism reciprocating motion was reduced by 21.47% at the maximum when the eccentricity was 7 mm and the connecting rod center distance was 82 mm, and the vibration of the eccentric shaft slider mechanism due to the inertial force was reduced. When the damping bodies were designed as nitrile rubber blocks with a diameter of 50 mm and a height of 20 mm, the displacement change of the cutter mechanism was 0.41 mm, which was less than 0.5 mm, which met the design requirements. The changing range of acceleration in x-direction of the cutter mechanism was reduced, and the sudden changing of acceleration in y-direction disappeared. The vibration of cutter mechanism was reduced. The die-cutting mechanism of roll-to-roll film automatic melting and assembling zipper equipment has small inertia force. It works stably and reliably. It is easy to be controlled by servo motor.