Foucault's Pendulum is a novel by Italian writer and philosopher Umberto Eco. It was first published in 1988, with an English translation by William Weaver being published a year later.

Umberto Eco was an Italian medievalist, philosopher, semiotician, novelist, cultural critic, and political and social commentator. In English, he is best known for his popular 1980 novel The Name of the Rose, a historical mystery combining semiotics in fiction with biblical analysis, medieval studies and literary theory, as well as Foucault's Pendulum, his 1988 novel which touches on similar themes.