The family of University of Maryland basketball star Len Bias, on the eve of the first anniversary of his death, filed a $27 million lawsuit yesterday alleging fraud and negligence by Bias' agent and the company that represented the all-America player in negotiations with the Boston Celtics and the Reebok shoe company.

The 54-page lawsuit, filed in D.C. Superior Court, claims that the family was denied potential life insurance benefits and payments from the shoe company because of poor management of Bias' accounts.

The suit said Lee Fentress and Advantage International, the agent and Washington-based company that represented Bias, "maliciously, intentionally and in reckless disregard of Len Bias' rights" led the Bias family to believe that the company had secured a $1 million life insurance policy for Bias.

The Biases had obtained a $1 million disability policy for their eldest son before he signed with Advantage International, but did not purchase life insurance for him because of Fentress' statements that he already had secured life insurance for Len Bias, the lawsuit says.

The suit also claims that the president of Reebok International Ltd., a Massachusetts-based athletic shoe company, made public statements that an endorsement contract between Reebok and Len Bias existed. But Reebok has denied that such a contract exists, the suit said, and has not paid the Bias estate any money. The lawsuit is seeking $2.6 million from Reebok.

Pam Lester, an attorney for Advantage International, said yesterday that she had not seen the lawsuit and could not comment.

Kate Burnham, a spokeswoman for Reebok, called the lawsuit "frivolous."

"What happened was a tragedy," Burnham said. "But our position is that there was no contract between Len Bias and Reebok International Ltd. We find that the lawsuit is frivolous, and we will defend it."

Fentress, a former assistant U.S. attorney in Washington who also represented former Maryland basketball coach Lefty Driesell, told James and Lonise Bias on separate occasions in April 1986 that he had secured a $1 million term life insurance policy for Len Bias, according to the lawsuit.

But Fentress, in an interview with The Washington Post in November, said that he did not recommend life insurance for Bias in the months before Bias was expected to sign with the National Basketball Association's Boston Celtics. Fentress said that was standard practice at Advantage, where he is a managing director.

Bias died of cocaine intoxication two days after his selection by the Celtics in the annual college draft.

Len Bias, according to the suit, was to be paid $325,000 a year for five years by Reebok, with the first installment of $162,500 due last June 18.

Bias never signed a contract with the company. But the lawsuit said that Fentress and Paul Fireman, the president of Reebok, had told James and Len Bias that an agreement had been made. And at a Reebok-sponsored reception honoring Boston Celtics players Dennis Johnson and Danny Ainge, the suit said, Fireman introduced Bias as "the newest member of our family."

The lawsuit also seeks damages of $1 million from the Fidelity Security Insurance Co. of Missouri for an alleged breach of contract. The Bias family in April 1985 obtained a $1 million disability insurance policy with the company that included an accidental death rider.

Bias' death last June 19 was the result of an accident, the suit alleges, and the company has not responded to a claim submitted by the Biases.

Wayne Curry, one of the lawyers representing the Biases, said that it was a coincidence that the suit was filed the day before the first anniversary of Len Bias' death. It took this long, Curry said, because of the long criminal investigation and trial resulting from Len Bias' death.

"We are not sure where all of these matters will lead," Curry said, "but we are absolutely certain that there is more to the story of Len Bias' demise."