Avinash Treebhoowoon and Sandip Moneea were found not guilty by a jury at the island's Supreme Court in Port Louis.
The daughter of Tyrone gaelic football manager Mickey Harte was found strangled in her room at the luxury Legends resort in January 2011.
In a statement, issued by both the Harte and McAreavey families immediately after the verdict, the families spoke of their devastation.
It read: ‘After waiting eighteen months in search of justice for Michaela and following the endurance of seven harrowing weeks of this trial, there are no words, which can describe the sense of devastation and desolation now felt by both families.
The families do not intend making any further comment until they return home to Ireland’.
The prosecution had claimed the defendants attacked the 27-year-old teacher when she interrupted them stealing in the room, having momentarily left her husband John at a poolside restaurant to fetch biscuits.
Treebhoowoon, 32, from Plaine de Roches, worked as a room attendant at Legends while Moneea, 43, from Petit Raffray, was his floor supervisor.
They were arrested at the hotel the day after the murder.
The high profile case was originally listed to run nine days but the verdict came in its eighth week.
Both verdicts were unanimous. 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 while relatives jumped to their feet cheering wildly.
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.
Outside court Treebhoowoon said he was overjoyed. He also expressed sympathy for the McAreaveys.
"I'm so sad about this lady," he said. "But I did not kill this lady."
Moneea wept as he hugged his lawyer Rama Valayden.
"I am so happy to be back with my family," he said. "These past 18 months have been so hard."
Supporters of the acquitted men let off fireworks at the front of the Supreme Court building as celebrations continued.
"I have been saved by the Lord Rama," Moneea shouted as he embraced his barrister.