To address the challenges faced in the traditional design and development process of the Aircraft Integrated Electromechanical Management System (IEMS)—including high workload, extensive documentation, and lack of unified design principles—a novel IEMS design approach based on Model-Based Systems Engineering (MBSE) is proposed. This approach improves upon traditional document-centric system engineering by mitigating issues such as heavy workload, overwhelming documentation, and fragmented design thinking; refining traditional IEMS design methods will contribute to the subsequent construction of IEMS models. Based on the operating principles of IEMS, the design methodology employs the Arcadia framework, facilitating a hierarchical modeling and mapping process across two domains including problem domain and resolution domain and four levels: operational analysis, system analysis, logical architecture, and physical architecture, and verify it. This approach demonstrates superiority in model construction, requirements tracing, and fault troubleshooting compared to conventional design methods. Future work aims to integrate the MBSE tool Capella with other platforms to achieve more scientific and more detailed modeling methods through simulation experiments.