Urdangarín y Liebaert grew up primarily in Barcelona with his older brother, and five sisters.
In 1986, he became a professional handball player for FC Barcelona, where he continued to play until he retired from the sport in 2000. He also participated in numerous Olympics as part of the Spainish handball team, he participated in the Summer Olympics in 1992 in Barcelona, 1996 in Atlanta, and in the 2000 Sydney Olympics(where he served as captain). The Spanish handball team won bronze medals in the 1996 and 2000 Olympics.
Also during his handball career, he studied at Escuela Superior de Administración y Dirección de Empresas (ESADE), where he earned a master's degree in business administration.
During the 1996 Summer Olympics in Atlanta, he met Infanta Cristina, the daughter of King Juan Carlos. They married on 4 October 1997. Upon their marriage, her father granted them the titles Duke Consort & Duchess of Palma de Mallorca. Together, they have four children, including:
- Don Juan Valentín de Todos los Santos Urdangarín y de Borbón (1999)
- Don Pablo Nicolás Sebastián de Todos los Santos Urdangarín y de Borbón (2000)
- Don Miguel de Todos los Santos Urdangarín y de Borbón (2002)
- Doña Irene de Todos los Santos Urdangarín y de Borbón (2005)
The family lived in Barcelona until 2009, when Iñaki's career brought the family to Washington, DC. The family returned to Spain in 2012.
Urdangarín y Liebaert is a member of the Spanish Olympic Committe, and has served as its deputy chairmain since 2004. He was awarded the Grand Cross of the Spanish Royal Order of the Sports Merit (The Real Orden del Mérito Deportivo) in 2001.
In November 2011, he was accused of diverting public funds for his own profit throng the Nóos institute in the 'Palma Arena case. In December of that same year, the Anticorruption Bureau confirmed that the Duke had been sending important sums of public money to tax havens in Belize and the United Kingdom and the Spainish Royal Court annonced that the Duke Consort would no longer participate in any official Royal Family activities as a result of the scandal. In 2012, he made several court appearances over the allegations. Since these allegations, he has been barred from attending royal events. In 2015, his brother-in-law renouced his and his wife's Dukedom.