Bob Woolf, the pioneering Boston-based sports lawyer who used what he called friendly persuasion to negotiate headline contracts for some of the nation's most famous athletes and entertainers, died on Monday night at a home he maintained in Hallandale, Fla. He was 65.

"He was watching 'Monday Night Football' and he just didn't wake up," his daughter Stacey Woolf-Feinberg said yesterday. "He was in the peak of health and had been playing tons of tennis." She said an autopsy would determine the cause of death.

Partly because he was one of the first sports agents, and partly because he brought to the profession both skill and a special sense of ethical responsibility, Mr. Woolf was one of the best known of his breed. Long List of Clients

If he never became quite as famous as the athletes and entertainers he represented, it was only because his client list tended to read like a catalogue of household names, among them Carl Yastrzemski, Larry Bird, Doug Flutie, Bernard King, John Havlicek, Ken Harrelson, Jim Plunkett, Julius Erving, Thurman Munson, Mark Fidrych, Jim Craig, Derek Sanderson, Robert Parish, Rocket Ismail, Ruben Sierra, Larry King and the New Kids on the Block.

Mr. Woolf was a young lawyer in Boston in 1965 when Earl Wilson, a Red Sox pitcher, asked him to handle his off-field activities, including endorsement contracts.

The next year, Mr. Woolf represented Wilson in his baseball contract negotiations, well enough that other athletes were soon seeking his services. In 1971 he abandoned the rest of his law practice and concentrated on representing athletes and other professionals.

One of his first major clients was Yastrzemski, the Red Sox slugger, who also became a close and generous friend. When he retired, Yastrzemski gave Mr. Woolf a wealth of his personal baseball memorabilia, which Mr. Woolf displayed proudly in his office on what became known as the Yaz wall. Office Overlooks Fenway Park

It was no accident that Mr. Woolf's office in the John Hancock building overlooked Fenway Park. Visitors who wondered whether the sports agent was a true sports fan had only to take a look through the telescope at his office window to find out: It was permanently aimed and focused on the Fenway mound and batter's box.

As his fame spread and his client list grew, Mr. Woolf, who estimated that he had negotiated more than 20,000 contracts by 1992, grew increasingly concerned by the spendthrift ways of young clients who didn't know the value of a million dollars.

Accordingly he often insisted on becoming the personal manager of the players he represented, overseeing their investments to make sure they would live comfortably after their peak earning years. He even went so far as to put his clients on allowances, or tried to. First-Class Allowance

Once, when Derek Sanderson, a notoriously fun-loving Boston Bruin player, took three friends on a first-class jaunt to Hawaii at a cost of $7,000, someone teased Mr. Woolf, saying he thought the agent had Sanderson on an allowance.

"I do," Mr. Woolf replied, "but Derek has an American Express card."

In addition to his daughter Stacey, a literary agent with her father's company, Mr. Woolf is survived by his wife, Anne, a daughter, Tiffany, and a son, Gary.

Robert G Woolf