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

• Alberto Martinelli, French President of the International Social Science Council
• Alessandro Martinelli (born 1993), Swiss footballer
• Alfredo Martinelli (1899–1968), Italian film actor
• Antonio Martinelli (c. 1702 – 1782), Italian violinist and composer
• Anton Erhard Martinelli (1684–1747), Austrian architect
• Arthur Martinelli (1881–1967), American cinematographer
• Caterina Martinelli (c. 1589 – 1608), Italian opera singer, employed by Duke Vincenzo I of Mantua
• Daniele Martinelli (born 1982), Italian footballer
• Dario Martinelli (born 1974), Italian musicologist and composer
• Davide Martinelli (born 1993). Italian professional road bicycle racer
• Domenico Martinelli (1650–1719), Italian architect (active in Austria)
• Elsa Martinelli (1935–2017), Italian actress and fashion model
• Enrico Martinelli (1852–1922), Italian trumpet player, teacher and composer
• Enzo Martinelli (1911–1999), Italian mathematician
• Ezio Martinelli (1913–1980), American artist
• Francesca Martinelli (born 1971), Italian ski mountaineer
• Franz Martinelli (1651–1708), Italian architect (active in Austria)
• Fred Martinelli (1929–2021), American college football coach
• Gabriel Martinelli (born 2001), Brazilian professional footballer
• Gaetano Martinelli (died 1802), Italian librettist active in the court theatres of Charles Eugene, Duke of Württemberg
• Gabriella Martinelli (contemporary), Italian-Canadian film and television producer
• Germaine Martinelli (1887–1964), French soprano
• Gianvito Martinelli (born 1969), Italian former professional racing cyclist
• Giovanni Martinelli (1600–1659), Italian painter of the Baroque era
• Giovanni Martinelli (1885–1969), Italian operatic tenor
• Giovanni Innocenzo Martinelli (1942–2019), Libyan bishop
• Giuseppe Martinelli (born 1955), Italian professional road bicycle racer
• Guido J. Martinelli Endara, Panamense economist and banker, member of the ONAREX
• Jean Martinelli (1910–1983), French actor
• Joe Martinelli (1916–1991), American professional soccer player
• Johann Baptist Martinelli (1701–1754), Austrian architect
• Julien Martinelli (born 1980), French professional football player
• Liliana Martinelli (born 1970), Argentine discus thrower
• Luca Martinelli (born 1988), Italian professional football player
• Lucas Martinelli Finazzi (born 1990), Italian Brazilian football midfielder
• Luigi Martinelli (footballer) (born 1970), Italian professional football player
• Luigi Martinelli (engineer), Italian academician, aeronautical and mechanical engineer
• Manlio Martinelli (1884–1974), Italian painter, active in Livorno
• Marco Martinelli (born 1965), Italian professional volleyball player
• Mario Martinelli (1906 –2001), Italian politician
• Marta Linares de Martinelli (born 1956), First Lady of Panama
• Mateo Martinelli (born 1985), Argentine Association football midfielder
• Nicola Martinellli Trometta (17th century; also called da Pesaro), Italian painter of the Baroque
• several people named Paolo Martinelli
• Pietro Martinelli, Italian cyclist
• Raffaello Martinelli (born 1948), Italian prelate of the Roman Catholic Church
• Renzo Martinelli (born 1948), Italian film director and screenwriter
• Ricardo Martinelli (born 1952), President of Panama (2009–2014)
• Rosario Martinelli (1941–2013), Italian professional football midfielder
• Sebastiano Martinelli (1848–1918), Italian Roman Catholic cardinal
• Sheri Martinelli (1918–1996), American painter and poet
• Thiago Martinelli (born 1980), Brazilian central defender
• Tommaso Martinelli (1827–1888), Italian Roman Catholic cardinal
• Tristano Martinelli (1555–1630), Italian actor in the commedia dell'arte tradition, probably the first to be called “Harlequin”
• Vincenzo Martinelli (1737–1807), Italian painter of canvas and fresco landscapes, active in Bologna

In fiction

• Janete Fontes Martinelli, interpreter of Liliana Castro in the Brazilian telenovela Caminhos do Coração, aired on Rede Record.
• Kate Martinelli, the fictional lesbian detective featured in novelist's Laurie R. King mysteries