Alexandra Margarita Russo is the only female out of the three Russo siblings, and the middle child. She is sly, rebellious, outgoing, and usually underachieves when it comes to school. She often gets into trouble because of her constant schemes (usually involving magic). She is part Latina and part Italian.

Even though she is infamously known for doing the worst in wizard studies and school, and relentlessly torments her older brother Justin, Alex became much more mature throughout the series. Although she's relatively lazy, Alex is very smart. She becomes the Russo family wizard at the end of the series. She goes through a long term relationship with Mason Greyback, a purebred werewolf that they break up numerous times but get back together.