SLJ or slj is a three-letter acronym that may refer to:
- IATA airport code for Stellar Airpark near Chandler, Arizona
- Samuel L. Jackson, American film and television actor and film producer.
- School Library Journal, an American monthly publication for school and public librarians
- Southern Literary Journal, a journal about the literature of the American South published by the University of North Carolina
- Spacelab-J, the joint NASA and National Space Development Agency of Japan mission STS-47
- Sports Lawyers Journal, a law journal published by the Sports Lawyers Association