Abstract: Cone pipe joints are widely used in electromechanical devices, and their sealing performance always affects the system reliability. Due to quantitative evaluation methods are studied rarely for the sealing performance of cone pipe joints, the design parameter impact rules are need to be investigated. In this paper, combing macro and micro perspectives, a quantitative evaluation method for sealing performance of cone pipe joints was proposed to investigate the impacts of design parameters on sealing performance. Firstly, in order to get the critical contact pressure for leakage channels disappearing, the Boundary Element Method (BEM) was adopted to simulate the contact behavior of the sealing interface during the assembly process. Then, to obtain the distribution and evolution of the contact pressure during the assembly process, an elastic-plastic finite element analysis was carried out for the tightening procedure. Finally, based on the critical contact pressure and pressure distribution, the effective sealing width was arranged to be obtained to evaluate the sealing performance quantitatively, i.e., under the same preload, the wider the effective sealing width, the better the sealing performance. And also, based on the effective sealing width, the impacts of the design parameters of cone pipe joints on the sealing performance were arranged to be quantitatively investigated. The analysis results show that the sealing performance of pipe joints with positive cone angle difference is better than the ones with negative cone angle difference and without cone angle difference. The sealing performance of pipe joints depresses with the increase of cone roughness. The sealing performance of pipe joints without cone roundness deviation is better than the ones with cone roundness deviation.