Spock Must Die! is an American science fiction novel written by James Blish, published February 1970 by Bantam Books. It was the first original novel based on the Star Trek television series intended for adult readers. It was preceded by a tie-in comic book line published by Gold Key and the novel Mission to Horatius by Mack Reynolds, all intended for younger readers.

James Benjamin Blish was an American science fiction and fantasy writer. He is best known for his Cities in Flight novels and his series of Star Trek novelizations written with his wife, J. A. Lawrence. His novel A Case of Conscience won the Hugo Award. He is credited with creating the term "gas giant" to refer to large planetary bodies.