French vessel "La Place", which is participating in the search for the plane, has picked up signal coming from deep in the sea and believed to be from one of the black boxes of the plane, an Egyptian committee investigating the crash said in a statement.
French investigators confirmed the news.
"The signal from a beacon from a flight recorder has been detected" by "La Place", said a French official.
A second ship, John Lethbridge affiliated with the Deep Ocean Search firm, will join the search team later this week, it said.
The cause of the tragedy still has not been determined.
The Airbus A-320's black box recorders could be critical in identifying the cause of the disaster.
EgyptAir flight MS804 disappeared from radar screens in the early hours of May 19, before it crashed into the Mediterranean Sea with all 66 passengers and crew on board presumed dead.
The search for the plane has been narrowed to a 5- kilometer -wide area in the Mediterranean Sea based on signals from the its emergency beacon.
Egypt has earlier said the likelihood of a terror attack was stronger than technical problems that caused the tragedy.
Leaked flight data indicated that a sensor detected smoke in a lavatory and a fault in two of the plane's cockpit windows in the final moments of the flight.
