Fonck is a surname. Notable people with this surname are:
- Bernard Fonck (born 1973), Belgian equestrian
- Catherine Fonck (born 1968), Belgian nephrologist and politician
- Raymond Fonck (born 1951), American Physicist and Professor
- Cecilia Bolocco Fonck (born 1965), Miss Universe 1987
- Johny Fonck (1920–2008), Luxembourgian athlete
- René Fonck (1894–1953), French World War I flying ace
- René Fonck (canoeist) (1923–2018), Luxembourgian sprint canoer