The Oscar-winning actor - who has been assisting in the country's relief efforts since it was struck by a devastating earthquake two years ago - will be awarded the 2012 Peace Summit Award at a ceremony in Chicago next month after being recognised for his work "to rebuild and aid the victims of the devastating 2010 earthquake in Haiti, as well as his ongoing advocacy for peace and human rights protection worldwide".
The 'Milk' star added in a statement: "This is an extraordinary honour in an extraordinary moment on Earth.
"It's difficult to properly respond to this while avoiding cliche, but quite deliberately, I'm thrilled to receive this tribute and to represent it to the youth of Haiti, the strong women of Haiti, and of the world.
"Tomorrow is a new day where cynicism is for cowards, and men of virtue and agency will be true heroes to their sons."
Earlier this year, Sean accepted the job of "ambassador at large" for the Caribbean nation.
He was offered the position by the nation's foreign minister Laurent Lamothe while at the Cinema for Peace benefit in Los Angeles in January.
Picking up a humanitarian award for his work in Haiti, he told the crowd: "I do accept [the job]," before adding it would be nice to be "called, 'Hey Mr. Ambassador.' "