Béla Károlyi (born September 13, 1942) is a Romanian gymnastics coach of Hungarian ethnicity. He was born in what was then Kolozsvár, Hungary, a region restored to Romanian administration after 1944. Károlyi and his wife, Márta, also of Hungarian origin, emigrated to the United States in 1981 and both have dual citizenships for Romania and the United States. The Károlyis have coached both Romanian and United States Olympic teams to medal-winning success.
Among the gymnasts Béla and Marta Károlyi have trained are Nadia Comăneci, Mary Lou Retton, Betty Okino, Kerri Strug, Teodora Ungureanu, Kim Zmeskal, Kristie Phillips and Dominique Moceanu. In total, Károlyi has coached nine Olympic champions, fifteen world champions, sixteen European medalists and six U.S. national champions.
Károlyi pioneered the Romanian centralized gymnastics training system in Romania in the late 1960s and early 1970s. He worked as a coach at the boarding school in Gheorghe Gheorghiu-Dej (now renamed Oneşti), training young girls especially chosen for their athletic potential. One of the first students at the school was six-year-old Nadia Comăneci, who lived near the town and commuted from home.