István Nagy may refer to:
- István Nagy (painter) (1873-1937), Hungarian painter
- István Nagy (writer) (1904–1977), Hungarian writer
- István Nagy (floristics) (1905–1974), Hungarian botanist
- István Nagy (actor) (1909-1976), Hungarian actor
- István Nagy (sculptor) (born 1920), Hungarian sculptor
- István Nagy (footballer, born 1939) (1939–1999), Hungarian footballer
- István Nagy (politician, born 1954) (born 1954), Hungarian politician
- István Nagy (athlete) (born 1959), Hungarian sprinter
- István Nagy (politician, born 1967) (born 1967), Hungarian agrarian engineer and politician
- István Nagy (ice hockey) (born 1981), Hungarian-ethnic Romanian ice hockey player
- István Nagy (footballer, born 1986), Hungarian footballer