Marelli is a surname. Notable people with the surname include:
Aldo Marelli (1919–2010), Italian professional football player Ercole Marelli (1867–1922), Italian engineer and entrepreneur Giovanni Tommaso Maria Marelli (1673–1752), Roman Catholic prelate Luigi Maria Marelli (1858–1936), Italian prelate Luisa Marelli Valazza (born 1950), Italian chef Marco Arturo Marelli (born 1949), Swiss set designer and stage director Michele Marelli (born 1978), Italian clarinet and basset horn soloist Sergio Marelli (1926–2006), Italian basketball player