Gillett is the name of several places in the United States:
- Gillett, Arkansas
- Gillett, Wisconsin
- Gillett (town), Wisconsin
- Gillett, Texas
- Gillett Grove, Iowa
Gillett as a surname may refer to:
- Fred Gillett, an astronomer who identified a planetary nebula in Messier 22 in 1986
- Frederick H. Gillett, former US Speaker of the House, US Representative and US Senator from Massachusetts
- James Gillett, a Republican politician and 22nd Governor of California from 1907 to 1911
- George N. Gillett Jr., an American businessman, owner of various sports teams