Vincent Promuto, a former Redskins football player, has won his Civil Service case against the U.S. Drug Enforcement Administration, which fired him last year for allegedly misusing government phones and filing false travel vouchers.

He appealed his dismissal to the U.S. Civil Service Commission, which ruled in 11 years until he retired in 1970, said yesterday that he plans to quit the agency, anyway, to practice law in New York and Washington.

"I made up my mind that I wanted to clear myself," Promuto said, "and that after I cleared myself I would resign. That's what I'm doing now."

Promuto, a public information officer for DEA since the agency was established in 1973, was fired in July, 1976, for alleged "dishonest conduct" in using government telephone lines and credit cards to make personal long-distance calls, and of making false statements on official travel vouchers.

He appealed his dismiisal to the U.S. CIvil Service Commission, which ruled in May that the agency had to reinstate him with back pay, and clear the charges from Promuto's record.

Frederick H. Pearson, a hearing examiner for the Commission, found that even though Promuto had used government phone lines to make several hundred calls to family memers and friends, the agency did not show he had the "specific intent to convert (government) funds which was necessary to prove "dishonesty."

Pearson said the travel vouchers contested by the agency either were correct or contained minimal error.

"The penalty imposed (firing) was excessive under the circumstances," Pearson declared, "and the decision of the agency to remove (Promuto) was arbitrary and unreasonable."

Yesterday Promuto said, "Just about everybody in government uses the phones for personal business. I didn't think it was costing the government any money, and when they told me about it, I offered to pay it back. If that was the reason they wanted to fire me, they could fire all of Washington for that reason."

Promuto said he felt he was the "victim of a power struggle" within DEA. He said that after he returned to his $35,000 a-year job at DEA's new York regional office in June, the agency refused to give him back pay and appealed the hearing examiner's ruling to the Civil Service Review Board. He said his lawyer, Irving Kator, filed a Freedom of InformationAct request for DEA records about his case.

Last week, Promuto said, DEA agreed to withdraw its appeal and give him back pay in return for his resigning by Aug. 31 and withdrawing the request for DEA Files.

William Lenck, executive assistant to DEA administor Peter Bensinger, yesterday confirmed the agreement but made no other comment on the case.