A metal-free direct trifluoromethylthiolation of sulfonium ylides with an electrophilic trifluoromethylthiolating reagent has been established, in which sulfonium salt or α-bromoacetic ester is employed as sulfonium ylide precursors. This trifluoromethylthiolation enables the straightforward construction of SCF3-substituted sulfonium ylides from a wide range of substrates, including ketones, esters, and even PEGylated substrates. Moreover, the application of this approach in large-scale preparation and the fluorescence and fluorine-19 magnetic resonance imaging capabilities of the product are also explored.