As of today, the federal governments is out of the business of controlling oil prices. But that does not mean the bureaucracy that did the controlling is also out of business.

President Reagan, his energy secretary, James B. Edwards, and his budget director, David A. Stockman, may soon find this out. Earlier this week Stockman predicted the order decontrolling oil prices that the president signed yesterday would allow the administration to "phase out . . . very quickly" the Department of Energy employes who administer the controls. Yesterday, Edwards said much the same thing although he admitted he did not know how many people would be affected.

But over at DOE, there is no horde of bureaucrats frantically searching for new jobs today and there may not be for some time. "You may have decontrol, but our operation is not going to end overnight," one was quoted yesterday.

There are a number of reasons for this, according to DOE officials. To begin with, by the usual standards of the federal bureaucracy, the control program did not involve a massive number of bureaucrats. Of DOE's 20,000 employes, about 1,750, or fewer than 10 percent, were involved in the control program in the department's Economic Regulatory Administration.

The bulk of these, about 1,500, are in two divisions charged with enforcing the regulations. They are lawyers, accountants, computer specialists, secretaries and clerks. And most will be staying right where they are, at least for a while.

The reason is that the department has a number of cases going on that involve alleged violations of regulations in the past. Those cases were not automatically wiped out along with the controls by yesterday's presidential action. Moreover, the 1973 law that established the controls authorizes the department to continue to investigate earlier violations even after the controls have been lifted.

The Reagan administration could, of course, halt ongoing investigations and prosecutions. Edwards declined to rule out this possibility yesterday.

A number of other DOE employes involved in monitoring aspects of the program also are likely to retain their jobs, as they have in the years since price controls were taken off home heating oil. These monitoring functions are expected to continue.

Eventually, however, many of job slots in DOE's Economic Regulator Administration will wither away, just as Reagan, Stockman and Edwards desire. But the bureaucrats themselves may be more difficult to get rid of. They are career civil servants and many can probably count on finding jobs elsewhere in the vast federal bureaucracy.

As a result of these factors, no panic was reported in the Economic Regulatory Administration as the president signed away many of its functions. "These people are not nearly as concerned as I thought they would be," one official said. "Maybe it's the nature of bureaucracy. They seem to be saying that maybe I'll be working under a different title, but they don't seem worried."