Considering the packaging requirements of different sizes of customized cartons, the design method of variable actuated layout for 5R parallel kinematic mechanism was proposed. The kinematic analysis of 5R parallel mechanism was carried out, and different workspace maps were drawn by geometric method. A method of searching the reachable workspace through tracing the motion trajectory was proposed. These provided the basis for configuration application of the carton packaging mechanism. The folding process of carton cover was analyzed, and the 5R mechanism of the two actuated motors with coincident joint was selected as finger prototype to fold the flap. The motion parameters of actuated motors were extracted through the motion simulation, the fitted analytic function was input into the control program of finger mechanism. The experimental results verified that the expected motion trajectory of carton flap and finger mechanism had good controllability. Thus a reconfigurable carton packaging machine was developed to demonstrate the ability to erect different sizes of the cartons, which was different from the production line. By means of restructuring module structure and reconfiguration control program, the end effector was flexibility and controllable. The device had the characteristics of small space occupation and flexible control. It would be helpful for the delivery staff to improve the working efficiency and reduce the workload.