Derek Hannon (born 3 August 1960) is the current Irish ambassador to the Holy See since he presented his Letters of Credence to Pope Francis on 9 November 2018.
He holds a degree in science of education, as well as a MA in history from University College Dublin.
He was posted abroad and served as part of the Irish delegation to the Holy See as third secretary from 1988 to 1992.
He returned to Dublin as first secretary at the Office for Anglo-Irish Affairs at the Foreign Ministry where he worked until 2004.
He was received by Pope Francis on 9 November 2018 to present his Letters of Credence on behalf of the Irish Government to begin his mission to the Holy See replacing Emma Madigan.