Cornett is a surname. Notable people with the surname include:
Abbie Cornett (born 1966), American politician Betty Jane Cornett (1932–2006), American baseball player Bill Cornett, American musician Brack Cornett (outlaw) (died 1888), American outlaw Brad Cornett (born 1969), American baseball player Flip Cornett (1957–2004), American guitarist Jonathan Webster Cornett (1883–1973), Canadian mayor Leanza Cornett (1971–2020), American television personality Marshall E. Cornett (1898–1947), American businessman and politician Mick Cornett (born c. 1958), American politician Mitchell Cornett, American politician Natasha Cornett (born 1979), American murderer R. Orin Cornett (1913–2002), American physicist Samantha Cornett (born 1991), Canadian squash player