Jeffrey Lionel Dahmer (; May 21, 1960 – November 28, 1994), also known as the Milwaukee Cannibal or the Milwaukee Monster, was an American serial killer and sex offender who killed and dismembered seventeen men and boys between 1978 and 1991. Many of his later murders involved necrophilia, cannibalism, and the permanent preservation of body parts—typically all or part of the skeleton.

Although he was diagnosed with borderline personality disorder, schizotypal personality disorder, and a psychotic disorder, Dahmer was found to be legally sane at his trial. He was convicted of fifteen of the sixteen homicides he had committed in Wisconsin and was sentenced to fifteen terms of life imprisonment on February 17, 1992. Dahmer was later sentenced to a sixteenth term of life imprisonment for an additional homicide committed in Ohio in 1978.

On November 28, 1994, Dahmer was beaten to death by Christopher Scarver, a fellow inmate at the Columbia Correctional Institution in Portage, Wisconsin.