Rt Rev Anthony Poggo will move to London from his current position as Bishop of Kajo-Keji.
He'll be joined by his wife Jane and youngest daughter Joy.
Speaking about the appointment, Most Rev Justin Welby said: "I am absolutely delighted that Bishop Anthony is joining the team at Lambeth.
"He brings the experience of his ministry in one of the most challenging provinces in the Anglican Communion where he has faithfully served the church as a pastor and teacher.
"Throughout his ministry he has engaged with the profound issues we face in many parts of the Communion, where famine, war, and violent ethnic tensions destabilise society and leave whole communities living in poverty."
His appointment comes following what Lambeth Palace describes as an extensive selection process which attracted applications from across the Anglican Communion.
Bishop Anthony said: "I am delighted to accept Archbishop Justin Welby's invitation and appointment to join the team at Lambeth Palace.
"I look forward to working together with colleagues at Lambeth to support the Archbishop of Canterbury in his ministry.
"I appreciate the support from Archbishop Daniel Deng Bul in releasing me from our current role in Kajo-Keji so as to make a contribution in the global Anglican Communion. Jane, Joy and I are excited at this next phase of our ministry."
Bishop Anthony has previously worked for Scripture Union and has been Bishop of Kajo-Keji since 2007.