The Prince George's County Board of Elections Supervisors threw out a referendum petition yesterday aimed at stopping the awarding of a county cable television franchise, saying the text of the petition was improperly worded.

The petition failed to include the language that all signatures were "genuine and bona fide," the board said, so it did not comply with Prince George's charter requirements.

Proponents of the drive immediately denounced the decision as "political" and promised to file suit against the board today.

"The board is attempting to thwart and frustrate the will of the voters," said Democratic Del. Timothy F. Maloney, an organizer of the drive. "They've attempted this four times in the past and they've lost four times," a reference to past petition efforts. "My God," he said, "you expect this kind of thing in Warsaw, not in Prince George's."

The three-member, politically appointed board, charged with overseeing all election and voter registration procedures, voted unanimously to direct its staff not to verify the 5,100 signatures already collected by the petition supporters in their effort to overturn the franchise award to Storer Cable Communications Inc.

Board attorney Ronald A. Willoner denied that the action was politically motivated. "The law requires strict compliance and the language is not there," he said.

Storer Cable, represented by former county executive Winfield M. Kelly Jr., won the right to build the county's northern-area system by a vote of the all-Democratic County Council last fall.

The company's plan had been rated third out of five proposals by the county's independent cable commission, and second by an independent consultant hired to evaluate the proposals. The award to Storer, as well as the southern-area franchise award to MetroVision of Prince George's County, were vetoed quickly by County Executive Lawrence Hogan. The council overrode the vetoes within hours after Hogan's action.

The petition group, called Citizens Against Backroom Legislation (CABL), organized hastily in an effort to bring the northern cable award before the voters in November. For the cable award to appear on the ballot, the group needed 10,000 signatures of registered voters.

The group had to submit one-third of the signatures last Friday, and the remainder by Feb. 22.

The board challenged the language of the petition because it failed to say the signatures are "genuine and bona fide." The petition distributed by CABL said: "I solemnly swear to the best of my belief, knowledge, and information, the signers are known to me to be qualified voters of Prince George's County."

The board said the petition had to contain both the "genuine and bona fide" statement as well as the one included by the group. Maloney declared this "redundant and unnecessary."

The board members are appointed by the governor. The sole Republican member, Charles C. Deegan, said he would ask the board's director to issue a sample petition in the future.