Gegan is a surname. Notable people with this surname include:
James Gegan Miller (born 1942), American physicist, engineer, and inventor Judy Gegan (born 1944), British swimmer Walter Gegan (1899–1931), American middle-distance runner
See also The Gegan, the islet near Seacliff Harbour, North Berwick, Scotland Nicholas McGegan (born 1950), British harpsichordist, flutist, conductor and early music expert Gehan