In the design and research of bionic squid, it is very important to study the hydrodynamic characteristics in the pitching posture, and the completion of pitching motion is the foundation for the realization of its behavior bionics, basic swimming motion and function.In order to study the hydrodynamic characteristics of the bionic squid's flexible tentacles in its pitching posture, the bionic squid was selected as the biomimetic object, and the flexible tentacle bending model at different pitching angles was established through the biomimetic squid simplified model.According to the 3D model, the hydrodynamic characteristics of biomimetic squid in different pitching postures and different bending degrees of tentacle were analyzed and compared by numerical simulation method.Through analysis:when the biomimetic squid uses flexible tentacle to coordinate swimming, it provides a favorable moment for the completion of its pitching posture, which is more conducive to the change of its pitching posture and swimming direction when it swims at high speed.When the bionic squid completes the pitching posture, it can adjust the posture and swimming direction more timely and efficiently by changing the bending degree of the tentacle, and it requires less energy consumption.The results may lay a foundation for the research on the flexibility and swimming behavior of biomimetic squid.