Erdei is the first boxer from Hungary to win world titles in two weight divisions.

Erdei turned professional in December 2000 and won the WBO Inter-Continental light heavyweight title in October 2002.

[2] Erdei defeated Giacobbe Fragomeni on 21 November 2009 for the WBC cruiserweight title.

After announcing his retirement in January 2010 and thus relinquishing his claim as Lineal light heavyweight champion, Erdei decided to have more matches in 2011 in the US and fought Samson Onyango and Byron Mitchell as his first opponents there.

[3] Erdei finally returned on 30 March 2013, losing a 10-round split decision to Denis Grachev.