In order to dynamically associate the decomposition of top-level parameters with the analysis of system-level performance in the space gravitational wave detection system,and to provide management and application analysis capabilities for the entire lifecycle information of space science tasks,a model-based system engineering(MBSE)method for managing parameters and analyzing detection performance in space gravitational wave detection systems was proposed.Parameter models for space gravitational wave detectors were constructed using the system modeling language(SysML),enabling the analysis of model content and recording of parameters after screening.Finally,an analysis was conducted on the detection performance of the space gravitational wave detection system for different scientific targets through detection sensitivity,which served as the main criterion for evaluating the detection ability of the system.The results demonstrated that the proposed method can enable the uniform management and tracing of all parameter contents,thereby supporting the demonstration of top-level parameters and the evaluation of system-level performance in the space gravitational wave detection system.