A SuFEx reagent was designed for chemoselective synthesis of unsymmetrical disulfide, featuring a triethoxysilane moiety and a sulfonyl fluoride group activated by a γ-sulfur atom. It reacts with a more acidic thiol to form a thiosulfonate intermediate, which then couples with a less acidic thiol. The reagent and residual base are easily removed by aqueous workup. This method enables synthesis of both unsymmetrical and symmetrical disulfides. Various unsymmetrical disulfides were synthesized in up to 98% yields using equimolar thiol starting materials, which surpasses SO2F2/Et3N-mediated protocol in efficiency and selectivity.