The other three people were missing but there were no signs of survivors, said fire department spokesman Leandro Palomeque.
The Beechcraft prop plane had just taken off from an airport near the Uruguayan resort city of Punta del Este when the aircraft went down yesterday.
It was carrying eight passengers, the pilot and a co-pilot.
The two crew members and seven of the passengers were Argentine, while the other traveler was a woman from Portugal, the air force said.
The cause of the crash was not immediately known but air traffic controllers said they saw an explosion shortly after takeoff.