Tesco Ireland boss Kari Daniels is to leave the company in April.
She will be replaced by Irish woman Natasha Adams, the supermarket group's current Chief People Officer.
Ms Adams will report to Tesco Group chief executive Irishman Ken Murphy, in a new role on the Tesco Executive Committee.
In a statement, Tesco said that after two decades with the business, Kari Daniels has decided to take some time out before deciding what to do next.
"I'd like to thank Kari for her significant contribution to our business during her time in Ireland and throughout her 20 years at Tesco," said Mr Murphy.
Tesco said the management changes here are in recognition of the strong performance, progress and significant future growth potential it sees for the market.
It follows two years of significant change in the supermarket sector here, driven by the pandemic.
Online grocery shopping has grown substantially as has the use of alternative services such as click and connect.
Supermarkets, including Tesco, also grew their market share as restrictions meant people could not eat out as much as before.
"The team has grown our ability to serve customers however, wherever and whenever they want to be served, through our market-leading online business and in our 151 stores nationwide," said Mr Murphy.
"All this and more has helped to drive strong online performance and sales growth on a two-year basis and sustained share growth in the market," he added.
Born in Kerry, Natasha Adams is to move back to Ireland with her family when she begins her new role.
"Natasha has made an outstanding contribution in her role as Chief People Officer, and her appointment to the new role of Chief Executive Officer, Tesco ROI, recognises the breadth of that contribution," Ken Murphy said.
"I have no doubt she will bring the same blend of strategic thinking and people-centricity as she leads our Irish business into an exciting future," he added.
