A copper-mediated trifluoromethylthiolation of alkenyl iodides with AgSCF3 has been developed. CuSCF3 species generated in-situ from a copper salt and AgSCF3 can be coupled with alkenyl iodides to produce the corresponding trifluoromethylthioalkenes efficiently. The reaction conditions are compatible with various functional groups. Moreover, its scale-up synthesis is also possible to provide the desired trifluoromethylthiolated product even on a gram-scale.