The former Glamorgan Head Coach had been in the post since August this year
Toby Radford has quit as National Academy and Performance manager for Cricket Ireland.
The former Glamorgan Head Coach also had roles with West Indies and the England Lions.
He took up his position with Ireland's Academy in August of this year.
Earlier in the summer, ex-Surrey Boss Chris Adams left the same position in May, within a day of his terms being agreed.