Petroleum science stands at a historic turning point: exploration extends to ultra-deep and deepwater frontiers, unconventional resources become dominant, and the dual imperatives of carbon neutrality and artificial intelligence are reshaping the industrial landscape and disciplinary boundaries. Building upon the “100 Grand Challenges in Petroleum Science” initiative launched by Petroleum Science in 2021, this paper presents a curated list of 100 fundamental scientific problems through systematic literature synthesis, expert deliberation, and multi-criteria selection. The challenges span six domains: exploration and development, transport and pipelines, refining and petrochemicals, materials science, carbon capture, utilization and storage-geothermal-hydrogen, and energy economics and digital transformation. In-depth analysis reveals three archetypes: mechanism-oriented problems that seek unified theories of multi-scale coupling, technology-oriented problems that push engineering limits under extreme conditions, and system-level problems that address full-chain integration and energy transition. A key insight is that artificial intelligence has evolved from an enabler to a core driver, and together with the low-carbon transition it is redefining the very paradigm of petroleum science. This roadmap is intended to guide research planning, investment, and talent development over the coming decades and to foster interdisciplinary collaboration on a global scale.