The decision was announced Saturday by UNESCO's world heritage committee in St. Petersburg, Russia.
"It's a big day for Acadie," Rene Legere, president of the National Acadian Society, said in an interview.
"This decision recognizes the beauty and heritage of Grand Pre, and also, an important (part) of the history of the Acadian people."
The National Historic Site of Grand Pre, situated in the province's picturesque Annapolis Valley, was settled by French colonists in the 17th century who came to be known as Acadians.
The area is home to some of the most extreme tidal ranges in the world, and early Acadian settlers used a complex system of dykes to make the land arable.
It became an area of great importance to Acadians after thousands were forcibly removed from the Maritime provinces between 1755 and 1763.
In addition to the national historic site, the newly designated area includes the communities of Grand Pre and Hortonville. It encompasses more than 1,300 hectares of land and properties.
In a release, Environment Minister Peter Kent said he was delighted with UNESCO's decision.
"This designation will attract not only Nova Scotians, Acadians and other Canadians, but also international visitors who are looking for unique experiences at iconic places," he said.
The release said Grand Pre was chosen because of "exceptional" cultural characteristics that are very important for present and future generations. It said the selection was years in the making.
"The recognition of the landscape of Grand Pre... is a significant community achievement and follows many years of hard work," said Bernard Valcourt, minister of state, Atlantic Canada Opportunities Agency and la Francophonie.
The UNESCO world heritage committee aims to identify and protect cultural and environmental heritage considered to be "of outstanding value to humanity."
Grand Pre joins a long list of iconic sites around the world, including the pyramids in Egypt, the Great Barrier Reef and the Great Wall of China.
Grand Pre qualified as a "cultural landscape."
Eleven of Canada's 16 UNESCO heritage sites are at least partially managed by Parks Canada.