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

• Alessandro Casati (1881–1955), Italian academic, commentator and politician
• Ambrogio Casati (1897–1977), Italian painter
• Domenico Casati (born 1943), retired Italian professional football player
• Francesco Casati (1620–1702), Roman Catholic prelate
• Gabrio Casati (1798–1873), Italian politician
• Gaetano Casati (1838–1902), Italian explorer of Africa
• Giulio Casati (born 1942), Italian emeritus professor of Theoretical Physics
• Luisa Casati (1881–1957), Italian patroness of the arts
• Mario Casati (born 1944), Italian boxer
• Michelle Casati or Michelle Torres, American retired professional tennis player
• Paolo Casati (1617–1707), Italian mathematician
• Pietro Casati (1891–1956), Italian racing cyclist