Aqueous amine-based chemical scrubbing has been considered the most promising near-term solution for CO2 capture from flue gas. However, its widespread implementation is hindered by the high cost associated with the parasitic energy consumption during solvent regeneration, along with degradation and corrosion problems. Computer simulations have been widely used to improve our fundamental understanding of CO2 absorption materials and processes in efforts to design and develop high-performance, cost-effective solvents. Here, we review recent progress in first-principles studies on molecular mechanisms underlying CO2 absorption into aqueous amines and solvent regeneration. We also briefly discuss aspects that remain unclear, such as degradation and corrosion mechanisms, and the reaction-diffusion behavior of CO2 at the solvent/gas interface. This review highlights the increasingly significant role of first-principles-based atomistic modeling in exploring the function and properties of candidate materials, as well as the complex physicochemical phenomena underlying CO2 capture, solvent degradation, and corrosion, especially when direct experimental characterization at the atomic level may be difficult.