We report an efficient, metal-free method for late-stage rapid [18F]trifluoromethyl radiolabeling of terminal alkenes at room temperature. Utilizing 3,3-difluoroallyl sulfonium salts as precursors, the process achieves high radiochemical yields (up to 94 ± 2%) in just 30 s, with excellent functional group tolerance. This method offers a simplified and efficient pathway to produce [18F]trifluoromethylated terminal alkene compounds, enabling their application in PET imaging and expanding the chemical space for drug discovery.