Helena Mattsson was born and raised in Stockholm, Sweden, with her two sisters. In her early teens she was discovered by one of the biggest modeling agencies in Sweden. After graduating from her Performing Arts High School in Stockholm, Helena traveled to London and New York to continue to study acting. Her big break came at the age of 19 when she left London for Los Angeles and was cast as the lead in the Warner Bros. comedy Sweden, Ohio (2004).

Mattsson recently had recurring roles on ABC's Desperate Housewives (2004) and CW's Nikita (2010). In 2012 she was cast as Alexis Blume in 666 Park Avenue (2012) for ABC.

Her feature film credits include: Seven Psychopaths (2012) with Colin Farrell, Guns, Girls and Gambling (2012) with Gary Oldman, Surrogates (2009) with Bruce Willis and Iron Man 2 (2010) with Robert Downey Jr..