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