G. Richard Pfitzner, the blunt-spoken and sometimes contentious Democrat who was named chairman of the Prince William County Board of Supervisors last January, said yesterday that he plans to relinquish that position after only one year.

"Rick is a fairly outspoken individual, and he uses a tone and buzzwords that tend to place him in the role of antagonist with people sometimes," said fellow Supervisor Edwin C. King, a Democrat.

King helped Pfitzner oust longtime Prince William Board Chairman Kathleen K. Seefeldt earlier this year, a political coup that Pfitzner said would give the board a greater say in managing the government of the fast-growing county.

But as chairman, Pfitzner, a Woodbridge lawyer, has clashed frequently with the county's business leaders and the local news media. "I think this has been a tough year politically in terms of governing Prince William County," said King.

In an interview yesterday, Pfitzner said his year as chairman had sapped him. "It'll wear you down," he said.

Despite the Democrats' 5-to-2 majority on the board, board members may choose Republican Supervisor Donald E. Kidwell from the Woodbridge District as the next chairman, some officials said. The seven supervisors select a chairman from their own ranks in the first board meeting each January.

Pfitzner, a former chairman of the County Democratic Committee, said he wants the board to establish a tradition of rotating the chairmanship on an annual basis, adding that he sees no problem with a Republican assuming the post. He would not comment on his choice for a successor.

King also said that he would accept a Republican chairman, although he declined to comment on whom he would support. He acknowledged that Kidwell wants the position.

Kidwell could not be reached for comment yesterday. He also helped to oust Seefeldt, who had held the chairmanship since 1979, and install Pfitzner.

Several Democratic legislators expressed surprise yesterday that members of the supervisors might support a Republican chairman.

"I would never approve of any shenanigans as that," said Del. Floyd C. Bagley of Dumfries, chairman of the County Democratic Committee. "I don't like it."

"Politically, that's a serious mistake," agreed state Sen. Charles C. Colgan. "As long as there's a Democratic majority, I think the chairman . . . should be a member of the [Democratic] party."