Nancy Sandra Sinatra (born June 8, 1940) is an American singer and actress. She is the daughter of singer/actor Frank Sinatra, and remains best known for her 1966 signature hit "These Boots Are Made for Walkin'".

Other defining recordings include "Sugar Town", the 1967 number one "Somethin' Stupid" (a duet with her father), the title song from the James Bond film You Only Live Twice, several collaborations with Lee Hazlewood, and her cover of Cher's "Bang Bang (My Baby Shot Me Down)" (lyrics and music by Sonny Bono), which features during the opening sequence of Quentin Tarantino's Kill Bill.