Abstract: To address the large unbalanced cable forces in conventional saddle-pylon systems of long-span suspension bridges, a main-cable-force self-propelled system and an innovative self-propelled saddle equipped with a row of rollers are proposed. Compared with traditional anti-slip saddle structures, the proposed system converts sliding friction into rolling friction and enables the self-balancing transmission of horizontal cable forces. However, the introduction of rollers significantly changes the load-transfer mechanism and may result in severe local contact stress concentrations, which could affect the service life and operational performance of the saddle structure. In this study, the newly developed self-propelled saddle was taken as a representative engineering case. A three-dimensional finite element model was established to investigate the contact stress distribution characteristics and was further verified using Hertz contact theory. The contact stress states of the rollers, saddle base, and pylon top surface were analyzed in detail. The results show that the contact stress distribution is highly non-uniform along the axial direction. The side rollers experience significantly higher contact stresses than the middle rollers, while the maximum stresses are concentrated near the edge regions of the contact surfaces. The observed stress concentration is mainly attributed to the fan-shaped upper saddle geometry and the thickness and inclination of the reinforcing ribs. Based on the identified stress-transfer characteristics, optimization measures concerning structural configuration and material selection are proposed to improve stress distribution and reduce local stress concentration. The proposed analysis framework and optimization strategy provide useful guidance for the design, assessment, and practical application of innovative self-propelled saddle systems in future ultra-long-span suspension bridges.