Alexa Ellesse Pena-Vega (born August 27, 1988) is an American actress, singer and pianist. She is best known for playing Carmen Cortez in Spy Kids film series and Shilo Wallace in the movie Repo! the Genetic Opera. In 2009, she starred as the title character Ruby Gallagher in the ABC Family series Ruby & The Rockits.

Alexa Vega was born in Miami, Florida. Her father is Colombian and her mother, Gina Rue, is an American former model. Vega has six siblings: paternal half-sister Margaux Vega (b. 1981), sister Krizia Vega (b. 1990), sister Makenzie Vega (b. 1994), maternal half-sister Greylin James (b. 2000), maternal half-brother Jet James (b. 2005), and maternal half-brother Cruz Hudson Rue (b. 2009). She moved with her family to California when she was four years old.