The Aaronic priesthood is the lesser of the two orders of priesthood recognized in the Latter Day Saint movement. The others are the Melchizedek priesthood and the rarely recognized Patriarchal priesthood. Unlike the Melchizedek priesthood, which is modeled after the authority of Jesus and the Twelve Apostles, or the Patriarchal priesthood, which is modeled after the authority of Abraham, the Aaronic priesthood is modeled after the priesthood of Aaron the Levite, the first high priest of the Hebrews, and his descendants. The Aaronic priesthood is thought to be a lesser or preparatory priesthood and an "appendage" of the more powerful Melchizedek priesthood.

In the Latter Day Saint movement, priesthood is the power and authority of God given to man, including the authority to perform ordinances and to act as a leader in the church. A group of priesthood holders is referred to as a quorum.