The Maryland Court of Appeals ruled yesterday that Gov. Marvin Mandel and his 1974 running mates will get back the $82,122 in amusement taxes collected by the state from the biggest fund raiser in Maryland history.

It could not be determined immediately to whom the $82,000 windfall will be refunded. Acting Gov. Blair Lee III, who was another beneficiary of the Four-Star Salute held May 22, 1973, in Baltimore, at which $849,625 was raised, said he was "not the one to decide" what will happen to the money.

The tax, representing 10 per cent of the proceeds of the affair, was collected belatedly after a complaint was voiced by Howard L. Gates, a political unknown. Gates said the state had collected amusement tax on his own fund raiser in June, 1973.

Yesterday's unanimous opinion reversed a Maryland Tax Court decision and agreed with a Circuit Court ruling that the tax should have not been collected because the only live entertainment provided at the massive event was organ music, for which two musicians were paid $130.

Contacted as he left the federal courthouse in Baltimore, where he is standing trial on political corruption charges, Mandel said, "I knew we were right all along," according to the Associated Press.

Among the organizers of the $100-a-person gala, which nearly filled the Baltimore Civic Center, were two of Mandel's corruption trial codefendants, Irvin Kovens and W. Dale Hess.

The $849.625 was used to help finance the succession election compaigns of Mandel, Lt. Gov. Lee, Comptroller Louis L. Goldstein and Attorney General Francis B. Burch.

Organizers of the affair were ordered to pay the tax more that a year after the event, when Burch's then deputy, Norman Polovoy, ruled that it was unimportant how much the musicians were paid. "They could have hired the New York Philharmonic, the Boston Pops, the La Scala for that kind of money," Polovoy said at the time.

But yesterday the seven-judge court, in an opinion written by Judge Marvin Smith, said that "playing a little bit of organ music behind a curtain under the circumstances of this case does not constitute a performance. Thus, no tax was due."