<p>Sliding electrical contacts are critical components in electrical connectors, brushes, and slip rings, with their performance directly influencing the reliability and stability of these equipment. Sliding electrical contact equipment operate in complex multi-field coupling environments involving Joule heating, frictional heating, thermal expansion, and sliding contact on rough surfaces. Current researches on the multi-field coupling mechanisms in sliding electrical contact are limited. This paper presents a numerical approach based on the boundary integration method to investigate the electro-thermo-mechanical coupling effects at the contact asperities of rough surfaces. The surface profile-dependent friction coefficient is considered through friction experiments. Using Fourier transform and the conjugate gradient method, the temperature, displacement, contact pressure, and electrical contact resistance (ECR) are calculated. The underlying influence mechanisms of surface parameters and loading conditions on the contact area, temperature rise, and ECR are systematically analyzed. This numerical approach provides insights into the multi-field coupling behavior in rough surface sliding electrical contacts.</p>