Who is the antagonist of To Kill A Mockingbird?

Bob Ewell is the antagonist.

"To Kill a Mockingbird" has two main characters: the narrator Scout and her father Atticus, the local lawyer. As the antagonist, Bob Ewell maliciously blames Tom Robinson, a black man, for raping his daughter, which sets the stage for the primary conflict with Atticus, who represents Tom at his trial.