Assuming you mean "What is the name of the actor who played Anakin Skywalker?", the answer depends on the movie. The role was originated by Sebastian Shaw in Return of the Jedi, and then Jake Lloyd played Anakin as a young boy in Phantom Menace. But the Anakin that most people remember was played by Hayden Christensen. He is voiced by Matt Lanter in The Clone Wars. The voice of Darth Vader was also done by James Earl Jones in the movies.
If you are referring to his "in-universe" name, then it is Anakin Skywalker.