Kádár (Hungarian, 'cooper', Hungarian pronunciation: [ˈkaːdaːr]) is a Hungarian surname which may refer to:

• Ján Kadár, Slovak-Hungarian film director
• János Kádár (1912–1989), Hungarian politician, top leader during the communist era
• Flóra Kádár (1928–2002), Hungarian actress
• Kálmán Kádár, Romanian water polo player of Hungarian descent
• Matthias Kadar, a composer of German-Hungarian descent
• Tamás Kádár, Hungarian footballer
• Zoltán Kádár, Romanian footballer of Hungarian descent
• Gyula Kadar, Hungarian military officer during world war two

• Kadar (disambiguation)
• Kádár (Hun judge)
• Kádár is the Hungarian name for Cadăr village, Tormac Commune, Timiș County, Romania