Jonestown was the short-lived settlement which was made in northwestern Guyana by the Peoples Temple, a cult from California, and which became lastingly and internationally notorious in 1978, when nearly its whole population died in a mass murder-suicide orchestrated by their leader, Jim Jones. The name of the settlement thus became, also, a term for that incident. The site is now an abandoned ruin.

Named after Jones, Jonestown was founded on his initiative in the mid-1970s, as an agricultural commune. It stood amidst jungle, about seven miles (11 km) southwesterly from Port Kaituma. Jonestown's population was about one thousand, once it was fully established and the bulk of Jones' followers had moved to it, but most of them lived there for under a year.

In November of 1978, United States Congressman Leo Ryan, accompanied by reporters and a delegation of concerned relatives of Peoples Temple members, visited Jonestown to investigate allegations of abuses there. The visit ended in the murders of Ryan and four others by members of the Peoples Temple, shot at the Port Kaituma airstrip as they were about to fly out. That evening, November 18, Jones led his followers in their mass murder-suicide. Somewhat over nine hundred men, women and children perished, Jones among them.

Jonestown was shortly abandoned by the collapsing remnant of the Peoples Temple. Afterward, it was at first tended by the Guyanese government, which allowed its re-occupation by Hmong refugees from Laos, for a few years in the early 1980s, but it has since been altogether deserted. It was looted but otherwise avoided by the local Guyanese, mostly destroyed by a fire in the mid-1980s, and its remains were left to decay and be reclaimed by the jungle.