Abstract: Fluorochemistry, as a critical strategic field, holds significant application value in industrial manufacturing and environmental protection. The fluorine footprint serves as an important indicator for assessing the environmental impact of fluorine emissions, encompassing industries such as fluorine chemical production, biomedicine, pesticides, and materials. In recent years, the ecological risks and human health concerns posed by emerging pollutants, particularly per- and polyfluoroalkyl substances (PFAS), have attracted global attention. Major economies, including the European Union, the United States, and China, have implemented stringent regulatory measures to drive the development of PFAS removal technologies and the exploration of alternatives. This review traces the historical development of fluorochemistry and the evolution of its technological paradigms, with PFAS as a focal point for fluorine footprint research. It examines the migration and transformation mechanisms of PFAS in environmental media, evaluates their ecological risks, and discusses their associated hazards. Additionally, the review synthesizes international regulatory policies and standard systems related to PFAS and provides an outlook on emerging technologies for their replacement and elimination.