Gavin Short, who heads the Falklands legislative assembly, said he believes voters will reject Argentina's claim to the group, The Independent reported. President Cristina Fernandez plans to take Argentina's case for sovereignty to the United Nations.
"I have no doubt that the people of the Falklands wish for the islands to remain a self-governing overseas territory of the United Kingdom," Short said. "We certainly have no desire to be ruled by the government in Buenos Aires, a fact that is immediately obvious to anyone who has visited the islands and heard our views."
Thursday is the 30th anniversary of Argentina's surrender in the Falklands War.
British Prime Minister David Cameron said he also has no doubt of the outcome of the vote. He said the British government did not suggest the referendum.
The group, known in Argentina as the Malvinas, is about 300 miles east of the South American coast and includes two main islands and hundreds of smaller ones.
The population is just over 3,000, and most residents are of British ancestry.