An 18-year-old Fairfax City man was charged yesterday with the shooting death of his father, whose body was found earlier yesterday on the floor of his bedroom, Fairfax City police reported.

Gary King, an unemployed high school dropout, according to police and neighbors, charged in the death of Louis King, 58, of 3530 Queen Ann Dr. in the Country Club Hills subdivision near Army-Navy Country Club and Fairfax High School. Young King was being held on $50,000 bond.

Police had no details on what might have led to the shooting, which they said occurred shortly after noon. The elder King died of a pistol wound in the chest, police said.

For about 20 years, before his retirement in January, King was a salesman at McKay Chevrolet, not far from his home in Fairfax City. Assistant sales manager Donnie Link said King "was the top man in sales."

Link said King was forced to retire because of disabling emphysema, a disease of the lungs.

Next-door neighbor Irene K. Woodward said King and his wife had separated 2 1/2 years ago. Mrs. Woodward, an agent for Panorama Real Estate, said the King house was just about to be put on the market as part of a settlement between the Kings.

"They were nice people, good neighbors and would have done anything for me," she said.

She said Gary King had dropped out of Fairfax High School during his senior year, and had been living with his father since June. Before that, Mrs. Woodward said, the young man had stayed with his mother who lived with her parents in Fairfax City.

Mrs. Woodward said King had told her he didn't know where he would settle after the house was sold.