An advisory commission to Gov. Harry Hughes today proposed sweeping changes in Maryland's divorce laws intended to make it easier to obtain a divorce, but also to encourage reconciliations of couples who have separated.

Bracing in advance for a loud political outcry, the group called for legislation that would limit the waiting period for divorce to one year after a couple has separated in all cases. Husbands and wives who do not mutually agree on divorce must now wait three years in many cases. The commission also recommended simplifying the legal grounds for divorce, which many now criticize as cumbersome and antiquated.

In addition, it proposed a relaxation of the present one-year ban on sexual intercourse between a husband and wife filing for an uncontested divorce.

"Let's not make any mistake. The recommendation being made here is a radical change in Maryland's divorce law. It will be extremely controversial in the legislature," warned House Speaker Benjamin L. Cardin (D-Baltimore), a commission member with intimate knowledge of political leanings in the state legislature.

Hughes could not be reached for comment today on whether he will agree to sponsor the proposals, which the commission has not yet drafted in final form, in the 1982 General Assembly session.

Several legislators predicted the proposals would have slim chances of passing in 1982, because it is an election year and divorce is always an explosive issue in Maryland, where the influential Catholic Church lobbies strongly against liberalization of divorce laws.

Maryland law now requires a three-year separation before a divorce unless both the husband and wife agree to dissolve the marriage, or unless one proves that the other committed adultery, desertion or one of five other legal grounds for divorce. The couple must remain separated "without any cohabitation and without interruption" -- which, the courts ruled, means without sexual intercourse. In an uncontested divorce, the separation must last for a year.

"Our laws are so antiquated that they force people into artificial situations," said Baltimore attorney Marvin J. Land, a commission member and former Baltimore County Circuit Court judge. "You have to tell couples: 'Try and reconcile, but for God's sake, don't have sex because that ruins your grounds.' " The waiting period must start all over again if the couple has had sex during separation, he explained.

Under the proposed changes, the waiting period for all divorces would be reduced to one year, except in adultery cases, in which divorce would still be granted as soon as adultery is proved. Also, the commission proposed doing away with all but two legal grounds for divorce -- adultery and separation -- since proving legal fault would no longer speed up the divorce process except in adultery cases.

And, in a move intended to encourage couples to reconcile, the commission proposed allowing cohabitation and sex during separation if it is part of a "bona fide attempt at reconciliation."

"Why penalize people more for having sexual intercourse with their spouses than with somebody else?" said commission chairman Beverly Anne Groner, a respected Montgomery County lawyer in the field of domestic law.

"This would take acrimony out of divorce litigation," said Kathleen O'Ferrall Friedman, a Baltimore lawyer with experience in divorce cases. "It will help both parties and the child not to suffer the bitterness they're subject to now." She said the complexity of proving legal grounds has kept some divorce cases in the Maryland courts for as long as seven years.

The commission, which includes lawyers, judges, lay people and legislators, was responsible for earlier proposals that led to laws enhancing the property rights of nonworking spouses in divorce cases and also liberalized alimony laws.

Today's proposal is likely to encounter a roadblock in the House Judiciary Committee, which rules on the fate of all divorce legislation.

"I'm not shot with enthusiasm about it," said Committee Chairman Del. Joseph Owens (D-Montgomery), who said he will oppose the proposal if it reaches his committee. Instead, Owens said he would be willing to support a reduction of the present three-year waiting period to two years, a proposal that has passed the House several times, and then died in the Senate.