Which Beyoncé album centers on a fictional alter ego named Sasha Fierce?

Beyoncé's album centered on the alter ego Sasha Fierce is I Am... Sasha Fierce.

Columbia Records released I Am... Sasha Fierce on November 12, 2008. The double album was divided into two discs: I Am..., which emphasized ballads and personal material, and Sasha Fierce, which presented more assertive, performance-oriented songs.

Beyoncé described Sasha Fierce as a stage persona she used while performing. The project included “If I Were a Boy,” “Halo,” “Single Ladies (Put a Ring on It),” and “Diva.” The album's title therefore refers to both Beyoncé's personal and stage-facing identities.

The album was a major commercial success and earned multiple Grammy Awards. Beyoncé later said that she no longer needed the alter ego because she had grown into the confidence Sasha Fierce represented.