Mascó got her start appearing in TV commercials in Spain. She was later signed to an agency and began modeling for print. Mascó appeared in the 1990 Sports Illustrated Swimsuit Issue as the cover model. She also appeared in the 1991, 1992, 1994, and 1995 editions. She played a supporting role in Después del sueño (After the Dream) and El largo invierno (The Long Winter of `39), two Spanish films from the early 90`s. In 2006 and 2007, she hosted the reality television show Supermodelo in Cuatro TV.

Mascó is regarded as one of the best Spanish models of the 90s and still appears in print occasionally. She`s also known for being involved in social causes. She is married to lawyer Eduardo Vicente and has four daughters, one of them an adopted girl from Haiti.