Teacher Michaela Harte was found strangled in her room at the luxury Legends Hotel during her honeymoon on the island in January 2011.
Hundreds of Donegal people attended her huge wake and funeral in sympathy with the well-known Harte family.
Both verdicts into the 27 year old’s murder were unanimous and jurors took two hours to deliberate.
Members of the McAreavey family walked straight out of court when the foreman of the jury made the verdicts known.
Both accused broke down in tears in the dock and their relatives cheered.
The high-profile case in Port Louis was originally listed to run nine days, but lasted eight weeks.
The prosecution had claimed that Mr Treebhoowoon and Mr Moneea attacked Mrs McAreavey when she interrupted them stealing from the room.
She had momentarily left her husband, John, at a poolside restaurant to fetch biscuits.
Mr Treebhoowoon, 32, from Plaine de Roches, worked as a room attendant at Legends, while Mr Moneea, 43, from Petit Raffray, was his floor supervisor.
They were arrested at the hotel the day after the murder.
There were chaotic scenes as the two acquitted men walked out of the court.
Throngs of people cheered “justice, justice” in Creole as policemen hurried the men through the courtyard.
Moments later defence lawyers were carried aloft.