The work aims to design a carton box opener with high working reliability and stability, so as to solve the problems of unreliable opening and poor working stability of box opener in the existing carton packaging production line. The functional requirements of the mechanism were analyzed and studied and the mechanism design method was adopted to design a multi-link mechanism to realize the work of taking, putting and opening the carton. The kinematics analysis of the designed box opening mechanism was carried out by the constraint equation of multi-rigid body dynamics. The ADAMS optimization design module was used to optimize the size of each link of the box opening mechanism. SolidWorks software was applied to design the prototype of the designed box opener. The motion of the box opening mechanism was simulated with the motion plug-in of SolidWorks. According to the simulation results, the mechanism could meet the automatic box opening function and the motion trajectory matched the trajectory of the motion equation solved by Matlab, which verified the accuracy of the mathematical model. When Matlab was adopted to solve the motion equation of optimized box opening mechanism, compared with the mechanism before optimization, the speed peak was reduced by about 34%, the acceleration peak decreased by about 75%, and the smoothness of the mechanism was greatly improved. The designed high-speed box opening mechanism not only meets the functional requirements of automatic opening, but also runs smoothly and works reliably, providing a more adaptable opening program for carton opening automation.