It will be the second successive year that the venue has hosted the event, which will run from June 30 to July 3.
This year, the Irish Open was won by Lucas Herbert by three shots.
Northern Ireland major winners Rory McIlroy and Graeme McDowell were part of the field along with the Republic of Ireland’s Shane Lowry.
Mount Juliet was set to host the Irish Open in 2020 before it was switched to Galgorm Castle due to the coronavirus pandemic.
The news comes following confirmation that the European Tour will be known as the DP World Tour from the start of the 2022 season and boasts total prize money of more than 200million US dollars (£147million) for the first time.
The lucrative Rolex Series expands from four tournaments to five with the addition of the Slync.io Dubai Desert Classic, while the season-ending DP World Tour Championship features a prize fund of 10m US dollars (£7.35m) – the first regular European Tour event with an eight-figure purse.