The Angel Moroni (/moʊˈroʊnaɪ/) is, in Mormonism, an angel who visited Joseph Smith on numerous occasions, beginning on September 21, 1823. According to Smith, the angel was the guardian of the golden plates, which Latter Day Saints believe were the source material for the Book of Mormon, buried in a hill near Smith's home in western New York. An important figure in the theology of the Latter Day Saint movement, he is featured prominently in Mormon architecture and art. Three Witnesses besides Smith also reported that they saw Moroni in visions in 1829, as did several other witnesses who each said they had their own vision.

Moroni is thought by Latter Day Saints to be the same person as a Book of Mormon prophet-warrior named Moroni, who was the last to write in the golden plates. The book states that Moroni buried them before he died after a great battle between two pre-Columbian civilizations. After he died, he became an angel who was tasked with guarding the golden plates and directing Smith to their location in the 1820s. According to Smith, he returned the golden plates to Moroni after they were translated and, as of 1838, Moroni still had the plates in his possession.