Supersonic flight offers significant potential to reduce long-range flight durations, enhance operational efficiency, and improve passenger comfort, thereby holding substantial development value. In recent years, it has emerged as a prominent research focus within aerospace science and technology. This study first establishes a methodology for calculating overall weight parameters for supersonic civil aircraft. The feasibility and accuracy of this approach are validated using the “Concorde” aircraft as a benchmark case. Building on this foundation, a sensitivity analysis framework is developed to evaluate the influence of key design parameters on aircraft performance. The sensitivity analysis reveals significant relationships between design variables and aircraft performance metrics. For instance, payload capacity demonstrates a direct proportionality with takeoff weight, where a 5% increase in payload results in a corresponding 5.6% increase in takeoff weight. Similarly, mission range exhibits a trade-off with fuel efficiency: extending the range by 3.4% leads to a 24% increase in takeoff weight and a 18.3% reduction in fuel efficiency. Cruise performance parameters also show notable sensitivities. A 1% increment in cruising Mach number decreases takeoff weight by 4.6% while improving fuel efficiency by 5.3%. Additionally, aerodynamic efficiency plays a critical role: a 1.4% enhancement in cruising lift-to-drag ratio reduces takeoff weight by 7.7% and increases fuel efficiency by 9.2%.From an economic perspective, engine-specific fuel consumption (SFC) demonstrates a strong influence on overall performance. A 2.5% reduction in SFC decreases takeoff weight by 12.6% and improves fuel efficiency by approximately 16%, highlighting the importance of optimizing propulsion systems. These findings provide valuable insights for the overall design and conceptual development of supersonic civil aircraft, offering practical guidance for future research and engineering applications.