The New Jersey Casino Control Commission today granted Resorts International Hotel Inc. a permanent license to run its lucrative gambling operation here, saying that the state had not proved that Resorts' past history made it unfit to run a casino.

The decision appears to ease the way for other companies with problems similar to Resorts' in their corporate histories to open up casinos in this once-fashionable seaside town..

Companies such as Bally, Caesar's World, Playboy and Penthouse want to open up casinos within the next few months. Some analysts forecast a $4 billion to $5 billion gambling industry here within the next few years.

Resorts had been grossing about $600,000 a day before taxes and expenses under a temporay license that would have expired at midnight tonight. It is thought to be the most profitable casino in the world.

Joeph P. Lordi, chairman of the five-member commission, said that he was concerned by some of the allegations Attorney General John Degnan made against Resorts -- most of them concerning operation of casinos in the Bahamas during the 1960s. Lordi said, however, that the preponderance of the evidence presented during 30 days of testimaony showed that Resorts was a responsible company with a good reputation.

Last December, Degnan's office recommended against granting Resorts a permanent license, charging that Resorts' Bahamian operations had been linked to organized crime in the mid-1960s and that the company cleaned up tis operation only when it was forced to by the Bahamian government.

Commissioner Albert Merck, who from his questioning and public statements during the hearings appeared most likely to vote against granting the permanent license, said afterward he was concerned because he saw "a number of contradictions and some real whoppers" in the company's testimony.

"We're not only granting them a license," he said, "we're conferring respectability on them. But there was just not enough [adverse evidence] to overcome the weight of the testimony."

Assistant Attorney General Michael Brown, who argued the state's case, said he was "disappointed," and that he disagreed with the decision. The state has 45 days to appeal.

Gamblers at the 197 tables and 1,354 slot machines in the Resorts casino appeared unfazed by the drama in the casino commission's hearing room three Boardwalk blocks away.

But in the hearing room the scene was tense, although Resorts officials' smiles showed their belief that the vote was a foregone conclusion. Scores of local businessmen and Resorts investors fretted that the commission would vote to turn down the license.

Resorts' stock, which, because of the hearing, did not trade until 3:05 p.m., ended up as the most active stock of the American Stock Exchange, closing up 4 3/4 at 47 3/4.

When Prospero DeBona, the fourth of the five commissioners to speak, announced he would approve the license, a sigh went through the crowd. Resorts needed four votes for the license.

After commissioner Merck, a chemical company heir who teaches at Drew University, made the vote unanimous, the audience applauded.

Resorts Chairman James Crosby said he was "gratified" by the decision and said that he knew from the beginning that the charges were "unfounded."

Among charges in a lengthy attorney general report were:

Resorts officials and some company employes had ties to racketeer Meyer Lansky in the mid-1960s, when Resorts officials that there had been casino. Lordi said that he agreed with Resorts officials that there had been no evidence of any "criminal involvement" on the part of Resorts officals and that Crosby, after taking over the casino, ahd gone out of his way to eliminate any corruption.

Former official Seymour Alter bribed a judge in New York and supplied prostitutes to Bahamian officials. Alter was suspended by the company a week after the attorney general's report appeared and the company has promised it will not reinstate him without the commission's approval.

Resorts President I. G. (Jack) Davis operated a slush fund to entertain Bahamian officials. Crosby testified that the fund -- of which about $26,000 was spent over a six-year period -- had been eliminated when he discovered it in 1972.