A temple garment, also referred to as garments, the garment of the holy priesthood, or Mormon underwear, is a type of underwear worn by adherents of the Latter Day Saint movement after they have taken part in the endowment ceremony. Garments are required for any individual who previously participated in the endowment ceremony to enter a temple. The undergarments are viewed as a symbolic reminder of the covenants made in temple ceremonies and are seen as a symbolic and/or literal source of protection from the evils of the world.

In Mormonism, the endowment is a two-part ordinance (ceremony) designed for participants to become kings, queens, priests, and priestesses in the afterlife. As part of the first ceremony, participants take part in a scripted reenactment of the Biblical creation and fall of Adam and Eve. The ceremony includes a symbolic washing and anointing, and receipt of a "new name" which they are not to reveal to others except at a certain part in the ceremony, and the receipt of the temple garment, which Mormons then are expected to wear under their clothing day and night throughout their life. Participants are taught symbolic gestures and passwords considered necessary to pass by angels guarding the way to heaven, and are instructed not to reveal them to others. As practiced today in the Church of Jesus Christ of Latter-day Saints, the endowment also consists of a series of covenants that participants make, such as a covenant of consecration to the LDS Church. All LDS Church members who choose to serve as missionaries or participate in a celestial marriage in a temple must first complete the first endowment ceremony.