As the energy sector undergoes rapid technological transformation, the resilience of electric power systems has become a focal point in the context of climate change and energy security. This paper examines the interplay between energy resilience and the digital upgradation of electric power systems in China, with a particular emphasis on the role of financial flexibility. Using panel data from 2005 to 2023 across 30 provinces in China, we employ the Generalized Method of Moments (GMM) model to investigate how financial flexibility—measured through capital access and adaptive financial strategies—affects the integration of digital technologies such as smart grids, renewable energy systems, and advanced monitoring infrastructures. Our findings demonstrate that financial flexibility significantly enhances the resilience of electric power systems by facilitating quicker adoption of digital technologies and enabling systems to better withstand external shocks, such as fluctuating energy demands and environmental stressors. The study offers policy insights, underscoring the importance of supportive financial mechanisms to accelerate the digital transformation and sustainability of China's energy infrastructure. This research contributes to the ongoing discourse on energy resilience by highlighting the critical role of financial flexibility in enabling technological advancements within the power sector.