The Church of Jesus Christ of Latter-day Saints, informally known as the LDS Church or Mormon Church, is the largest Latter Day Saint denomination. Founded by Joseph Smith during the Second Great Awakening, the church is headquartered in Salt Lake City, Utah, and has established congregations and built temples worldwide. As of 2023, it has over 17.2 million members, more than 6.8 million of whom live in the U.S.

The church was founded as the Church of Christ in western New York, in 1830 by Smith. After Smith's 1844 death and a resultant succession crisis, the majority of his followers sided with Brigham Young, who led the church to its current headquarters in Salt Lake City. Young and his successors continued the church's growth, expanding first throughout the Intermountain West, and then as a national and international organization.

The church has faced criticism throughout its history, including its past practice of polygamy, which was curtailed in 1890 and officially rescinded in 1904. Modern criticism includes disputes over the church's historical claims, treatment of minorities, and finances.

Church theology is restorationist and nontrinitarian. The church identifies as Christian, believing in the doctrine of salvation through Jesus Christ and his substitutionary atonement on behalf of mankind. It is often included in lists of larger Christian denominations, though some Catholics, mainline Protestants, and evangelicals consider it distinct from mainstream Christianity.

The church has an open canon of four scriptural texts: the Holy Bible, the Book of Mormon, the Doctrine and Covenants (D&C), and the Pearl of Great Price. Church members adhere to laws of sexual purity, health, fasting, and Sabbath observance, and contribute ten percent of their income to the church in tithing. Ordinances taught by the church include baptism, confirmation, the sacrament, priesthood ordination, endowment, and celestial marriage.

Members are known as Latter-day Saints or informally as Mormons. They believe the church president is a modern-day "prophet, seer, and revelator" and that Jesus Christ leads the church by revealing his will to its president. The church has a hierarchical structure and a volunteer clergy, with male members ordained to the priesthood and women occupying leadership roles in some church organizations. Both men and women may serve as missionaries.