The introduction of trifluoromethylthio (SCF 3) and trifluoromethylseleno (SeCF 3) substituents into organic molecules significantly improves the electron-withdrawing and lipophilic properties of their parent compounds. Therefore, a vast class of versatile reagents were employed to access the corresponding fluorine-containing compounds. Among them, tetramethylammonium salts, such as (Me 4 N)SCF 3 and (Me 4 N) SeCF 3 , have been employed as practical and efficient non-metal reagents for developing efficient trifluoromethylthiolation and trifluoromethylselenolation in recent years. This Minireview systematically illustrates the application of (Me 4 N)XCF 3 (X=S, Se) in the synthesis of trifluoromethylthiolated and trifluoromethylselenolated compounds, and its content is divided into two categories: transition-metalcatalyzed reactions, and transition-metal-free reactions. Scheme 13. Metal-free trifluoromethylthiolation and trifluoromethylselenolation of alkynyl(phenyl) iodoniums with (Me 4 N)SCF 3 and (Me 4 N) SeCF 3. [45] Scheme 14. Metal-free trifluoromethylthiolation of arenediazonium salts with (Me 4 N)SCF 3. [46] Scheme 15. Catalyst-and additive-free trifluoromethylselenolation of organic halides, diaryliodonium triflate, aryldiazonium tetrafluoroborates and αdiazo carbonyls with (Me 4 N)SeCF 3. [49] Scheme 16. Metal-free trifluoromethylthiolation of cyclic sulfamidates with (Me 4 N)SCF 3. [50] Minireview 69