With the escalating requirements for load adaptability, working condition stability, and dynamic response speed of special vehicles, the design complexity and performance requirements of their hydraulic systems have been significantly improved. The traditional document-based systems engineering (DBSE) approach, which suffers from long design iteration cycles, poor multi-condition adaptability, and insufficient data traceability, can no longer meet the design and development requirements of new-generation special vehicles. To address these limitations, this study applies the Model-Based Systems Engineering (MBSE) method to the design phase of the special vehicle hydraulic system and establishes an MBSE-driven design model to support real-time system verification. The research systematically carries out three-layer hierarchical modeling, including system requirement analysis, functional modeling, and logical architecture design. This study demonstrates that, in the development of special vehicle hydraulic systems, the model-based design method exhibits significant advantages in early requirement verification, rapid functional simulation, and full-link data traceability, thereby effectively improving the overall efficiency of system design, while reducing the trial-and-error cost in the development stage.