To address the issues of existing underwater robots being prone to damage and low operational efficiency in complex terrains and strong current environments， and to meet the demand for full-cycle exploration and maintenance in oil and gas development， this paper designs a bionic crab underwater robot， fabricates a 1∶1 conceptual model， and investigates the rationality of the design. Taking the crab as its bionic prototype， the robot adopts a streamlined body to reduce flow resistance. It uses the combined drive of walking legs and thrusters to achieve multi-degree-of-freedom movement on the seabed. Its front claws and appendages can remove obstacles， and the biological prototype structure provides excellent impact resistance. The model is fabricated using fused deposition modeling （FDM） and stereolithography （SLA）3D printing. After modeling， simplification and splitting in Rhino， components including legs， body and claws are printed separately and then assembled as a whole. Verified by computational fluid dynamics （CFD） simulations and wave-making experiments， this study lays a foundation for the physical implementation of the robot. In the future， integrating AI and new materials will enable it to adapt to deeper-sea operation scenarios.