gem-Difluoroalkenes are unique structural motifs with important applications ranging from drugs to materials. Herein, we report a novel radical-mediated defluorinative allylation of sulfamate esters with α-trifluoromethyl alkenes through distal C(sp3)−H functionalization under photoredox conditions. The reaction could readily incorporate various gem-difluoroalkene motifs into previously unfunctionalized sp3 carbon centers. The transformation allows directly dual activation of N−H and C(sp3)−H bonds via a photocatalytic and redox-neutral process, as well as using water as environmentally friendly co-solvent. The reaction could provide a general and operationally simple method to access gem-difluoroalkene compounds with high diversity.