The Old Catholic Church affirms an ordained priesthood distinct from the laity. Priests are sacramentally ordained through the laying on of hands by bishops and receive a permanent character enabling them to celebrate the sacraments and lead the church. This priesthood is genuine, though subordinate to Christ's eternal priesthood and the priesthood of all believers affirmed in Scripture.

Uniquely among historic churches claiming apostolic succession, the Old Catholic Church permits married clergy at all levels, including bishops. This practice was recovered from the early church (many apostles and early bishops were married; clerical celibacy developed later). Married clergy enhance the church's witness to the goodness of marriage and the redemption of embodied human life. Most national Old Catholic churches (in Austria, Germany, Switzerland, etc.) have permitted married priests since the church's inception.

Since 1996, most Old Catholic branches have ordained women to the priesthood, becoming among the first historic churches to do so. This decision reflects the church's commitment to justice, equality, and the gospel's message of liberation. Women exercise the full sacramental priesthood alongside men. A few Old Catholic branches have not adopted women's ordination, permitting theological variation. The ordained ministry is understood as servant leadership exercised in communion with the laity and under episcopal oversight.