Colnaghi is a last name. Notable people with this last name include: Ignazio Colnaghi (1924–2017), Italian actor Luca Colnaghi (born 1999), Italian racing cyclist Martin Henry Colnaghi (1821–1908), British art dealer Mattia Colnaghi (born 2008), Italian racing driver
See also P. & D. Colnaghi & Co., an art dealership in England