Based on the single cabin inerting flushing model and MATLAB language, A system level performance analysis tool was designed and developed for the civil aircraft fuel tank inerting system. The tool integrates the bleed air source pressure interface database,the automatic generation model of flight parameters and ASM performance data table, and it also includes the optimization algorithm for the minimum NEA flow under large flow mode during descent stage according to the acceptable landing oxygen concentration within the fuel tank. Through the application of this tool, this paper studies the quantitative effect of bleed pressurization form, NEA flow, tank ventilation form, oxygen concentration limit on ASM quantity and bleed air flow for inerting system with full tank inerting, comprehensively compares the performance requirements of the system under open ventilation architecture and closed ventilation architecture, and provides a trade-off method reference for the architecture design of civil aircraft fuel tank inerting system.