Subdeacon is a minor order of ministry for men in various branches of Christianity. The subdeacon has a specific liturgical role and is placed below the deacon and above the acolyte in the order of precedence.

In Christianity, minor orders are ranks of church ministry. In the Catholic Church, the predominating Latin Church formerly distinguished between the major orders —priest, deacon and subdeacon—and four minor orders—acolyte, exorcist, lector, and porter. In 1972, the Vatican re-titled the minor orders as "ministries", with those of lector and acolyte being kept throughout the Latin Church. In the Eastern Orthodox Church, the three minor orders in use are those of subdeacon, reader and chanter.