The Doors of Perception is an autobiographical book written by Aldous Huxley. Published in 1954, it elaborates on his psychedelic experience under the influence of mescaline in May 1953. Huxley recalls the insights he experienced, ranging from the "purely aesthetic" to "sacramental vision", and reflects on their philosophical and psychological implications. In 1956, he published Heaven and Hell, another essay which elaborates these reflections further. The two works have since often been published together as one book; the title of both comes from William Blake's 1793 book The Marriage of Heaven and Hell.

The Doors of Perception provoked strong reactions for its evaluation of psychedelic drugs as facilitators of mystical insight with great potential benefits for science, art, and religion. While many found the argument compelling, others including German writer Thomas Mann, Vedantic monk Swami Prabhavananda, Jewish philosopher Martin Buber, and Orientalist scholar Robert Charles Zaehner countered that the effects of mescaline are subjective and should not be conflated with objective religious mysticism. Huxley himself continued to take psychedelics for the rest of his life, and the understanding he gained from them influenced his final novel Island, published in 1962.