Vietnam veteran Charles Liteky, a recipient of the Medal of Honor, is so upset over congressional plans to appropriate aid for the Nicaraguan contras that he will renounce his honor dramatically at a Capitol Hill press conference today.

Following that, Liteky, 55, a former Roman Catholic chaplain, will go to the Vietnam Veterans Memorial and place the medal in an envelope to rest against the base of the monument. The former Army major, who was presented the medal in 1968, said yesterday he'll miss it and the benefits he will lose, such as a $200 monthly stipend, free medical care and free military transportation anywhere in the world. But Liteky said returning the medal is his way to protest U.S. intervention in Central America. Cruising Along at 55

If Zsa Zsa Gabor didn't exist, someone in Hollywood would have created her and no one would have believed the creation. She is about to be married an eighth time. This latest husband-to-be is Prince Frederick von Anhalt, Germany's duke of Saxony. Gabor says the prince is 45 and she is 55 -- which would have made her the youngest Miss Hungary at the ripe old age of 5. According to the Film Encyclopedia, she won the title in 1936. The encyclopedia, however, lists her birth date as "Feb. 6, 1920(?)."

"I went through so many rich men and young men, it's time to settle down," she said. "The older ones are impotent and the young girls don't know the difference." Technically Gabor contends she's only had three husbands -- hotel magnate Conrad Hilton, actor George Sanders and Turkish Minister Burhan Asaf Belgee. "The other four were only legalized love affairs," she said. "My mother Jolie told me, 'Just because you want to have a love affair, you don't have to marry the man.' But as you see, I am not following her advice as usual." Out and About

Hospital Report: Jazz great Ella Fitzgerald is in good condition at Niagara Falls Medical Center, where she is undergoing testing to determine if she suffered a mild heart attack. The 68-year-old singer was taken to the hospital Sunday following a concert the previous night. When she arrived at the hospital her condition was diagnosed as congestive heart failure. Fitzgerald was hospitalized when she was here last summer for a fluid buildup in her lungs. A Niagara Falls hospital spokesman said about 150 calls, including one from the White House and one from jazz singer Mel Torme, have come in inquiring about Fitzgerald's condition . . . Sen. Barry Goldwater went home this weekend from the Walter Reed Army Medical Center where he was treated for abdominal pain last week. The 77-year-old one-time presidential candidate underwent a series of tests . . .

The flamboyant Warner LeRoy, famous for New York's Maxwell's Plum and Tavern on the Green, will have a splashy opening tomorrow for the Potomac, his new restaurant on the Georgetown waterfront. There will be acrobats and high-speed, expensive Cigarette boats racing about on the river. Joining him for a seven-course meal, he says, will be such celebrities as authors Kurt Vonnegut Jr. and Peter Maas, television newsmen Peter Jennings and David Brinkley, Sen. John Warner, Mayor Marion Barry and Secretary of Defense Caspar Weinberger . . .

Rolling Stone Keith Richard and his wife, model Patti Hansen, announced the birth of their second daughter yesterday at New York City Hospital. The still-unnamed girl weighed in at 9 pounds 2 ounces. Their first daughter Theodora was born March 5, 1984 . . .

Former Watergate reporter Carl Bernstein is in a battle with his New York landlord, who has now gone to court to try to evict him. Bernstein moved into a $4,000-a-month brownstone on East 62nd Street five months ago and has written a number of letters to his landlady Guida De Carvalhosa complaining about faulty electricity and plumbing, noisy workmen and a crumbling ceiling. With some of the complaints, Bernstein has refused to pay some of his rent. Carvalhosa has filed a civil suit seeking his eviction. She also says he is behind in payment of rent, charging he owes $4,000 . . .