Princess Anne spent more than an hour talking to staff and clients of Brooke House.
The royal visitor was entertained by a music group which included harpist Eileen Beamish.
She was greeted on arrival by Lord Brookebrough and the chief executive of Brooke House, Joan Clements.
It was one of a number of engagements planned for the Princess Royal on her third visit to Northern Ireland this year.
“It was a wonderful honour to welcome The Princess Royal to what we are proud to describe as an oasis of peace and our sanctuary for healing,” Clements said.
“We want veterans to know there is this professional organisation waiting to deliver a whole host of confidential services to help them overcome their challenges, aid recovery and develop resilience.”
During her trip to Fermanagh, Princess Anne visited Church of Ireland and Roman Catholic churches in Irvinestown
As president of the Commonwealth War Graves Commission, she paid her respects to RAF veterans by observing moments of reflection.
She met serving RAF personnel, RAF cadets, and groups of community representatives.
The 85th anniversary of the Air Training Corps was marked.
