Aluko, who made 102 appearances for England and played in three World Cups and two European Championships, was previously director of women's soccer at English side Aston Villa.
"This is an incredible opportunity to help write Angel City's first chapter and to build a team that is people-focused and admired by players and fans all over the world," said the 34-year-old, who played for Chelsea and Juventus among other teams.
In July, the NWSL said it had awarded the exclusive rights to bring a team to Los Angeles to a group of founders that included actress Natalie Portman, tennis great Serena Williams and more than a dozen former U.S. women's national team players.
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Banana thrown at Richarlison during Brazil's win over Tunisia
"I have no doubt the club will be a trailblazer, not just in the NWSL and women's soccer, but for sports clubs globally," Aluko said.
As a former player, the club's determination to make an impact both on the field and in the community is something that I fully support, and I can't wait to get started.
The club announced in October that tennis great Billie Jean King and Olympic ski champion Lindsey Vonn had joined the team's star-studded cast of investors.
"I'm thrilled to join a fantastic female-led ownership group, many of whom I have admired and been inspired by from a young age," said Aluko, who became a lawyer after her retirement in 2020.
The franchise will become the NWSL's 11th team when they begin playing in 2022.
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