Selena Marie Gomez ( born July 22 , 1992 ) is an American actress and singer . She is best known for playing Alex Russo on the Disney Channel series , Wizards of Waverly Place . Selena Marie Gomez ( born July 22 , 1992 ) is an American actress , singer , and UNICEF Goodwill Ambassador , best known for portraying Alex Russo in the Emmy Award-winning Disney Channel television series Wizards of Waverly Place .