AIB's group chief executive Michael Buckley has announced he will retire at the end of June.
Mr Buckley, who formally announced his retirement date today, will be succeeded by Eugene Sheehy.
In a statement, AIB said: "Earlier this year Michael Buckley indicated that the length of the handover period between him and the new chief executive would depend on whether an internal or external candidate was selected.
"The appointment of Eugene Sheehy, who has over thirty years experience in a variety of roles with AIB, means that a lengthy transition is not necessary and Michael Buckley has, therefore, decided to retire as chief executive at the end of June this year."
The statement said that at the request of Mr Sheehy, Mr Buckley will continue as AIB's representative on the board of M&T bank until April of next year.