Abstract: In order to solve the problem of holding pike crabs after fishing, the crab claw of pike crabs need to be tied up individually, and crab claw gathering is important for crab claw binding. In this study, a bionics-based crab claw gathering device for pike crabs was designed, which is inspired by the natural movement of Portunus crab claws. After a careful analysis of the physiological structure of crab claw, we understood the characteristics of their activities well, and then designed this bionics-based crab claw closing device. The device tested the pincer closing for 10 Portunus crabs of different body masses, and 8 individuals were successfully closed. For the crabs with size of 133 mm³ and body mass over 130 g, the effect is better. Thus, the device provides a preliminary and effective solution to effectively solve the problem of Portunus crab claw closing.