Suspended Maryland Gov. Marvin Mandel acknowledged yesterday that he owes about $40,000 to his former wife in overdue alimony payments. At the same time, he asserted he could not pay her.

"I owe the money," he stated in court papers filed yesterday. "I don't know how much clearer I can say it. I owe that sum of money. I haven't paid it and I haven't paid anything isnce and I owe the money."

Mandel, who faces a four-year prison term, has said before that he is broke.After he was convicted last year of political corruption, he escaped the heavy fines meted out to most of his codefendants, claiming he was penniless.

According to the court papers, he will argue the same thing next week at a hearing scheduled to settle the matter of who must pay Barbara Mandel the alimony awarded her when her husband left her in 1973 to marry another woman.

"I fully intended to pay it," Mandel asserted in the paper filed as a preliminary to the hearing, "unfortunately I couldn't."

Barbara Mandel is also suing millionaire Irvin Kovens, a former friend of hers and the closest man to Marvin Mandel. Only with Koven's guarantee payment of their divorce settlement, Barbara Mandel claims, would she have left the governor's mansion and allowed her ex-husband to marry Jeanne Dorsey.

"I only signed the guaranty to guarantee $135,000, that's all," said Kovens in a document filed yesterday.

The entire settlement, as revealed last week in papers filed in the suit, is worth about $500,000.

Actually, according to testimony at Mandel's trial, Kovens paid $150,000, and the prosecution argued that it was in return for Mandel's manipulation of the legislature to benefit a race-track owned by Kovens and other defendants. Kovens also faces a four year sentence.

Kovens said in the papers he filed in Barbara Mandel's suit, "I was friends with both of them," meaning both Marvin and Barbara Mandel.

Barbara Mandel contended in papers she filed that Kovens, as guarantor, must pay the $1,562.50 due her twice a month as well as the attorney's fee covering the suit she has brought.

She claims she has not been paid since May 1977 for any of the divorce settlement. "During the trial he (Mandel) was not making his payments but I did not want to cause him any problems then," she said.

"But I'm surprised Mr. Kovens and Mr. Mandel haven't gotten together and figured out how to be decent and fair to me."