Tellurium hexafluoride is a chemical compound of tellurium and fluorine with the chemical formula TeF₆. It is a colorless, highly toxic gas with an extremely unpleasant smell.

Tellurium hexafluoride is most commonly prepared by passing fluorine gas over tellurium at 150 °C. Below this temperature a mixture of lower fluorides form, including tellurium tetrafluoride and ditellurium decafluoride. It can also be prepared by passing fluorine gas over TeO₃ or indirectly by reacting TeO₂ with SeF₄ to produce TeF₄ and then heating TeF₄ in excess of 200 °C to make TeF₆ and Te.

Tellurium hexafluoride is a highly symmetric octahedral molecule. Its physical properties resemble the sulfur and selenium analogs. It is less volatile, however, due to the increase in molecular weight. At temperatures below −38 °C, tellurium hexafluoride condenses to a volatile white solid.

Unlike the sulfur analog, tellurium hexafluoride is not chemically inert. This can be attributed to the larger atomic radius which can co-ordinate a maximum of eight atoms rather than six for sulfur and selenium which allows for nucleophilic attack. TeF₆ is hydrolyzed in water to Te(OH)₆ and reacts with Te below 200 °C.

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