This study proposes a spatio-temporal evolution-based methodology for anti-cracking safety evaluation and intelligent temperature control in 300 m-class super-high arch dams. Addressing limitations in traditional anti-cracking safety coefficient methods—such as neglect of dynamic spatiotemporal safety distribution, material performance gaps between laboratory and field conditions, and oversimplified stress calculations—an integrated approach is developed. Key innovations include six critical process curves (temperature, autogenous deformation, strength, structural stress, allowable stress, and anti-cracking safety coefficient) for dynamic lifecycle control, and an intelligent temperature gradient strategy (“small gradient, slow cooling, precise control”) targeting spatiotemporal thermal stress mitigation. Validated through applications in Xiluodu, Wudongde, and Baihetan dams, the methodology achieves zero thermal cracking while reducing cooling water usage by 15–20% and energy consumption by 7 kWh/m3. Case studies demonstrate compliance rates of 99% for peak temperature control and 96% for internal block temperature differences. The framework extends to projects like TB and NY dams, offering a scalable solution for thermal cracking prevention in large-scale hydraulic structures through harmonized material innovation, adaptive cooling protocols, and real-time monitoring systems.