Lutetium(III) fluoride is an inorganic compound with a chemical formula LuF<sub>3</sub>.
Lutetium(III) fluoride can be produced by reacting lutetium oxide with hydrogen fluoride, or reacting lutetium chloride and hydrofluoric acid:
It can also be produced by reacting lutetium sulfide and hydrofluoric acid:
Lutetium oxide and nitrogen trifluoride react at 240 ðC to produce LuOF. A second step happens below 460 ðC to produce LuF<sub>3</sub>.