In order to solve the problems of great labor intensity, low working efficiency, etc. in the process of kelp seedling clamping operation, a new type of kelp seedling clamping machine was designed, with the aims to automation of the process of seedling and rope buckle breaking, clamping of post-transplanting seedling and restoration of seedling and rope, etc.. This paper introduces the mechanical structure, the technics and working principle of the machine. And post-insertation executive structure was also designed. The kinematical simulation analysis of operation process was performed by applying the stimulation software. The results showed that the ideal feeding length of seedling and rope buckle breaking was 60-80mm; torque of rope clip and seedling clamping rope should be less than 4.2N-m; when the buckle was broken, the larger the torsion angle is, the larger diameter of the rope is; adopting the clamping of post-transplanting seedlings could increase the survival rate of post-insertion seedlings and reduce t the rate of damage to the seedlings. The design of a new type of mechanical system of kelp seedling clamping can provide references for the development and application of the planting device of marine plants.