Rueda was born in Madrid. Her father was a civil engineer and her mother was a ballet instructor. She is the second of three children; her siblings are named Chus and Violeta (Ms. Rodal). She and her family moved to San Juan, Alicante when she was a child because of her younger sister's asthmatic problems. She was married to Daniel Écija and had three children with him, Beliá (b.1994), María (b.1996) and Lucía (b.1998); unfortunately, their second child died of a heart disease as a baby. She is now a divorcée. When Rueda was 18 years old she moved to Madrid to study architecture, but she left the university when she met an Italian man whom she later married. Rueda returned to Madrid and worked as a salesperson and a model until she finally became a TV presenter. After that she worked as an actress on television, including the show Los Serrano, and eventually acted in films. She won a Goya Award in 2004 for her role as Julia in Mar Adentro (The Sea Inside). She received another Goya nomination for her role in the 2007 film, The Orphanage. Rueda played the lead role of the Spanish thriller Los ojos de Julia, which is produced by Guillermo Del Toro.
