The Heart Is a Lonely Hunter is the debut novel by the American author Carson McCullers. It is about a deaf man named John Singer and the people he encounters in a 1930s mill town in the US state of Georgia.

The book begins with a focus on the relationship between two close friends, John Singer and Spiros Antonapoulos, deaf-mutes who have lived together for several years. Antonapoulos becomes mentally ill, misbehaves, and, despite attempts at intervention from Singer, is eventually put into an insane asylum away from town. Now alone, Singer moves into a new room.

The remainder of the narrative centers on the struggles of four of John Singer's acquaintances: Mick Kelly, a tomboy who loves music and dreams of buying a piano, Jake Blount, an alcoholic labor agitator, Biff Brannon, the observant owner of a diner, and Dr. Benedict Mady Copeland, an idealistic physician.