Lawyers for Health and Human Services Secretary Margaret Heckler and her estranged husband John Heckler today were unable to reach an out-of-court settlement in the five-week-old divorce trial, according to lawyers involved in the case.

Lawyers anticipated that bargaining would continue throughout the evening and did not rule out a settlement. Barring that, however, they expect to be back in court tomorrow.

It had been thought that Margaret Heckler would take the stand for the first time today but before she could, Judge Edmund V. Keville called her and John Heckler into his office for a 75-minute meeting. Keville then adjourned court for the day to give lawyers an opportunity to resolve the property dispute at issue.

Heckler had emerged teary-eyed from Keville's chambers after the meeting and announced that lawyers would meet in nearby Boston this afternoon to discuss a settlement. She was dressed in a purple suit and black fur coat and was accompanied by three security guards.

"We will make every effort to settle this," Heckler said as she sat in the courthouse hallway, fingers clutching a Styrofoam cup. "I'm certainly willing to settle." Less than 20 yards away, a grim-faced John Heckler stood in a corner with his own lawyers. Husband and wife did not speak.

John Heckler, 57, has portrayed himself in numerous interviews as a male version of the political wife -- a helpmate and strategist who watched with growing anger as the couple grew estranged. His lawyers' opening statement also included admission of his infidelity.

She is seeking a share of her husband's property, which includes majority stock in his Boston-based investment banking firm as well as the couple's 19th-century colonial house in Wellesley and a two-story condominium in Rosslyn. Both the house and the condominium are mortgaged and it is the investment firm as well as Margaret Heckler's own assets that have been most at issue in the case.

The investment firm, Boston Institutional Services Inc., reported sales of $9 million last year. John Heckler is contesting his wife's claim to a share of the company. Margaret Heckler's lawyers have estimated the value of his holdings to be $4.8 million. His attorneys have placed the value of his holdings at $1 million. One of them today said tomorrow's testimony will include an estimate of the company's value made by Margaret Heckler two years ago when she filed financial disclosure forms before becoming a member of the Reagan Cabinet. At that time, according to John Heckler's attorney, Mark Sandground, Margaret Heckler put the value of BISI at $595,000.

Margaret Heckler claims that her husband's business profited by her political career.

John Heckler has described his wife as a "millionairess" and his lawyers have attempted to estimate a value of a Cabinet position against future earnings. Margaret Heckler's attorneys have put the worth of her federal retirement benefits at a cash value of $158,080. John Heckler disputes that. His lawyers have stated that the pension is worth $425,000.