General Accounting Office, the congressional watchdog agency that pokes federal fat and pinches pennies for Uncle Sam, says the government would save money if long-frozen $50,000 executives got raises of up to $7,500 due them.

Indeed GAO, in the diplomatic language one must use when telling the boss he has fouled up, makes the case that Congress' tightwad approach to executive pay has doubled some federal compensation costs that are borne by all taxpayers, whether they be clerks at Commerce or lumberjacks in Oregon.

Top government-military pay has been "capped" (by Congress) for the past several years at $50,112.50. Rank-and-file feds got a 9.1 percent raise last year, and 4.8 percent last month. Most military people got even bigger raises. The result is that generals and admirals make the same as some who salute them, and 40,000 government workers -- from the middle to the top of the bureaucratic totem pole -- get the same size biweekly paycheck.

The "cap" language limiting top pay to $50,112.50 is part of a continuing resolution that expires next Friday. If Congress passes a new stopgap bill -- to fund agencies whose budgets have not been cleared -- without the "cap" language, frozen federal executives, generals and admirals would be entitled to an immediate raise of just over 22 percent. That represents raises denied them for the past three years, raises that other civilian and military personnel got.

The political problem for Congress is that removal of the "cap" would also raise pay of representatives and senators. Many members of Congress favor executive branch-military raises, but fear the backlash if they too get raises. The irony is that because voters and newspaper editorials make it so painful for Congress to give itself above-board raises, it is becoming a millionaires' club. The rich find it easier to run, keep two homes and entertain the way elected officials (who get $60,115.50) feel they must to keep getting elected.

Pay raises for government executives may be decided this week. That is when Senate-House conferees meet to iron out differences in a new stopgap money bill that will fund government operations through February of 1982. Or until Congress passes agency budgets.

Because this is action week, the GAO endorsement of executive-military pay raises comes at a critical time.

Comptroller General Charles A. Bowsher (head of the GAO) has written Chairman Ted Stevens (R-Alaska) on the subject of top federal-military pay. Stevens is majority whip of the Senate and chairman of its civil service subcommittee. By virtue of his duties senators with less knowledge (or interest in) things bureaucratic listen to Stevens like the people in TV commercials listen to E.F. Hutton on stocks. Stevens favors executive raises. He has a plan he hopes will please the Senate and House and give top people their first paycheck improvement in years. Bowsher's letter will make his case easier to plead.

The GAO chief says the freeze on top pay while rank-and-file wages go up has created an "absurd situation." Absurd situations don't always bother Congress. But what he says next, that it is costing money, may swing some weight with this Congress and administration, which worships at the shrine of cost-effectiveness.

Bowsher says the pay cap is pushing some of Uncle Sam's best and brightest into costly early retirement. While they enjoy retirement pay, people are brought in, at top salary, as replacements.

"Experienced executives at the peak of their managerial career are retiring at alarmingly high rates; 3,137 top executives retired in 1980, compared with only 508 in 1977. Besides the lost expertise and continuity," Bowsher wrote, "such retirements are very expensive. Not only must executives' retirement annuities be paid for a longer period, but salaries must be paid to their replacements as well. Thus, for each exercutive who retires, the government must actually pay two persons -- the retiree and his or her replacement -- to get one job done."