Guarnieri is an Italian surname. Notable people with the surname include:

• Adriano Guarnieri (1914–1983), Italian alpine skier
• Adriano Guarnieri (composer) (born 1947), Italian classical composer
• Adriano Guarnieri (born 1979), Eye doctor and researcher
• Albert Guarnieri (1899–1980), American football player
• Albina Guarnieri (born 1953), Italian-born Canadian politician
• Anna Maria Guarnieri (born 1933), Italian actress
• Antonio Guarnieri (1880–1952), Italian classical cellist and conductor
• Camargo Guarnieri (1907–1993), Brazilian composer
• Danilo Caro Guarnieri (born 1965), Colombian trap shooter
• Ennio Guarnieri (1930–2019), Italian cinematographer
• Gianfrancesco Guarnieri (1934–2006), Brazilian actor, lyricist, poet and playwright
• Giuseppe Guarnieri (1856–1918), Italian physician
• Jacopo Guarnieri (born 1987), Italian cyclist
• Johnny Guarnieri (1917–1985), American musician
• Luiz Carlos Guarnieri (born 1971), Brazilian footballer
• Rodolfo Guarnieri (1927–2019), Argentine former sports shooter
• Umberto Guarnieri (1919–20??), Italian footballer

• Guarneri, family of luthiers from Cremona