Michael Jude Byrnes (born August 23, 1958) is an American prelate of the Catholic Church who served as Archbishop of Agaña from 2019 to 2023.

Beginning in 2004, he served as vice rector of Sacred Heart Major Seminary in Detroit as well as a parish pastor.

[4][1] On October 31, 2016, Byrnes was appointed by Pope Francis as coadjutor archbishop with special faculties of the Archdiocese of Agaña.

[6] Although Archbishop Anthony Apuron of Agaña was found guilty on charges of the sexual abuse of minors by an Apostolic Tribunal of the Congregation for the Doctrine of the Faith on March 16, 2018, he was only suspended from the exercise of his authority over the archdiocese and retained his title pending the outcome of his appeals.

[11][12] On March 28, 2023, Pope Francis accepted Byrnes' resignation as archbishop of Agaña for medical reasons.