WASHINGTON (AP) _ The Justice Department announced today that a Lebanese man has been charged in the United States with taking hostages in the seizure of a Royal Jordanian Airlines plane in Beirut, Lebanon, 2 1/2 years ago.

''This represents the first overseas arrest by U.S. law enforcement officials of a suspected terrorist being sought under U.S. laws,'' Attorney General Edwin Meese III said in a statement released to the press.

Meese was scheduled to hold a briefing on the matter later in the day.

Meese said Fawaz Younis was arrested Sept. 13 by special agents of the FBI in international waters in the Mediterranean Sea.

The suspect was flown to the United States in military aircraft and arrived at Andrews Air Force Base today, Meese said.

He appeared before a U.S. magistrate in the District of Columbia charged with hostage-taking, conspiracy and destruction of an aircraft.

The charges stem from a June 11, 1985 incident at the Beirut International Airport in which passengers and crew of Royal Jordanian Airlines Flight 402 were taken hostage. At least four U.S. nationals were aboard the aircraft when it was hijacked.

Meese said the hostage-taking statute provides ''long-arm'' jurisdiction over offenses committed outside the United States where U.S. nationals are among those taken hostage.

Meese said the arrest was the culmination of an operation carried out by the Justice Department and the FBI.

''It is a major policy goal of the United States government that we bring to justice those who are accused of being responsible for terrorist crimes,'' Meese said.

He said that under laws enacted by Congress in 1984 and 1986 the United States has the authority to investigate and prosecute individuals suspected of committing specific types of offenses under U.S. law in foreign jurisdiction.

''It is the first such operation but it will certainly not be the last,'' Meese said.