Objective In the actual metro construction, it is often necessary to lay turnouts on large-slope sections due to planning and construction constraints, land conservation or topographical limitations. However, it is found through practical application that the large-slope turnout structure leads to poor train stability and ride comfort during operation, thus an investigation on the factors influencing vehicle passing performance through large-slope metro turnouts is required. Method Based on multi-body dynamics theory, using simulation analysis software and taking the No.9 turnout installed on a 30‰ slope as research object, a coupled vehicle-turnout multi-body dynamics model is established. The dynamics performance indicators (including wheel-rail interaction, safety indicators, and stability indicators) of single vehicle passing through large-slope turnout at different operating speeds and friction coefficients are compared，aiming to analyze the impact of various factors on the vehicle passing performance through large-slope metro turnouts. Result & Conclusion It is revealed through simulation research that the impact of operating speed on wheel-rail interaction, stability indicators, and safety indicators is independent of the slope direction during vehicle passing turnouts. When a vehicle passes through turnouts on uphill and downhill slopes, the influence trends of operating speed on the dynamics indicators are consistent, with a more significant impact when going downhill; the friction coefficient greatly affects the wheel-rail dynamic interaction and the vehicle lateral acceleration. As the friction coefficient increases, the wheel-rail interaction force decreases, the carbody vertical acceleration shows no significant change, and the lateral acceleration increases significantly, with a more pronounced effect when going downhill. Therefore, certain strengthening and protective measures should be taken when vehicle going downhill.