The former CEO of Liverpool Airport will take up his new position in June.
As chief commercial officer of the Vantage Airport Group, Thomas has been responsible for leading the implementation of its business development strategy.
Most recently in New York, he played a leading role in winning the $4 billion redevelopment contract of the Central Terminal at La Guardia Airport, the largest public-private-partnership in the United States.
He was also at the forefront of negotiations at other major US airports including JFK, Chicago and Denver as well as in the Bahamas.
In his role with Vantage he was also responsible for the development of its existing portfolio of eight airports across four countries, and was a Board member of Lynden Pindling International Airport in Nassau, Bahamas, and John C Munro Airport in Hamilton, Toronto.
As CEO of Liverpool John Lennon Airport he led a number of key transformational projects, including a major terminal redevelopment, attracting new airlines and routes and the creation of an award-winning people development strategy.
Shannon Grpup chairman, Rose Hynes, says: “I am delighted to announce Matthew’s appointment as the new CEO of Shannon Group plc. He brings to the role a deep knowledge of the aviation industry combined with significant commercial experience.
"He combines pragmatic, effective management with strategic purpose and has an excellent track record of success.
"We are very fortunate to have secured an executive of Matthew’s ability and proven international experience to drive our strategic agenda, not just for the benefit of Shannon Group, but for the benefit of the Irish economy as a whole.”
Matthew Thomas says: "I'm excited to be coming to Shannon and Ireland at this time, and to have this opportunity to share my diverse experience with the Shannon Group.
"Shannon has an iconic place in aviation history. It is the gateway to The Wild Atlantic Way, and I know that it is very important to both the regional and national economy.
"I'm looking forward to working with my new colleagues in Shannon, the Board of Directors and all of the stakeholders to ensure the Group grows and makes the impact the West of Ireland deserves."