To study the bearing capacity and arch foot cracks of reinforced concrete truss arch bridges, taking a certain large-scale reinforced concrete truss arch bridge as the research background, by conducting a visual quality inspection, the types and locations of defects were identified, the causes were analyzed. A finite element model of the entire bridge is established, a scheme of reinforcing the transverse connecting components by pasting steel plates is proposed, and the main arch structure is strengthened by using an increased section method of external steel plates combined with low shrinkage self-compacting micro expansion concrete; a refined local finite element model is established for the arch foot area with multiple intersecting bars, complex stress states, and severe crack propagation. The stress state and crack propagation characteristics of the arch foot position before and after reinforcement are systematically analyzed. Research has shown that after reinforcement, the load-bearing capacity of the bridge structure is significantly improved and meets the requirements of the specifications. The width of arch foot cracks is effectively controlled and the distribution range is significantly reduced. The reinforcement scheme has achieved significant engineering results and economic viability, and the research