The Central Intelligence Agency, whose public image and private morale have been battered during much of the past decade, appears to be regaining some of its lost money, manpower and maneuvering room under the Reagan administration.

In Director William J. Casey, a long-time friend and political adviser to President Reagan, the agency has perhaps more clout in the White House than ever.

In its deputy director, Adm. Bobby Ray Inman, the former chief of the super-secret National Security Agency, the CIA has one of the nation's most respected professional itelligence officers to brush up the analytical product and keep tabs on technological prowess. Some senior CIA officials believe that Casey, 68, may not stay in his post for Reagan's entire four-year term and that Inman is heir apparent.

In Vice President Bush, the agency has another godfather at the highest levels of government. Bush, a CIA director under President Ford who is, according to agency officials, very proud of his days at the agency, played a key role during the transition period in helping turn Reagan toward the CIA.

Bush, insiders say, convinced a reluctant president-elect Reagan to let the CIA brief him every day on the global intellignece picture -- even when he was in California -- so that the president would quickly develop a feel for the evolution of events rather that be exposed only to special or occasional situations.

CIA's secret, multibillion-dollar budget is going up substantially.Though sources say this actually began in the final year of the Carter administration after events in Iran and Afghanistan, it is clear that it will keep going up under Reagan.

Officials say the agency, for the first time in years, has money to hire analytical specialists for areas of the world previously neglected, for more linguists, and to pay for more trips abroad by analysts.

The agency is also expanding its most secret clandestine, covert and paramilitary operations overseas, according to agency sources. This expansion, however, is supposedly going slowly because it requires experienced people and lengthy preparation.

Sources say the expansion of clandestine activites also began in the last Carter years after the president overcame his suspicions of the CIA -- suspicions that officials claim flowed largely from Vice President Mondale, a former member of the Senate committee headed by then-senator Frank Church that investigated allegations of CIA abuses in the mid-1970s.

Casey, many insiders say, is most interested in the agency's clandestine operations. His appointment last month of Max Hugel, a New Hampshire businessman who worked with Casey on the Reagan campaign, as CIA's deputy director for operations caused much grumbling throughout the intellignece community.

Hugel has no experience in spy operations, but his post is the most sensitive in the CIA and involves overseeing the agency's entire overseas spying operations. Many intelligence officers, active and retired, were aghast at putting an amateur in such a job, while a few others thought it mostly an attempt to jolt the crusty world of spying with some business world experience.

But things have quieted down and one veteran intelligence officer offers a differenct way to view the appointment. In this view, Casey, a high-ranking officer overseeing intelligence operations in Europe in World War II, wants to run the clandestine operations himself and wants only a trusted friend between him and the operations.

Whether this means that CIA eventually will return to its heyday of covert intervention abroad, including assassination attempts, as well as its occasional dabbling in domestic activities on the fringe of its charter, is not known.

While the improvement in the overall situation at CIA is seen by many officials as necessary to bolster U.S. intelligence, the largest problem for the agency, and for the government and citizenry as well, may come in keeping the CIA from once again going too far afield within an atmosphere far more congenial than that of the mid-1970s.

The key document that is supposed to define what the CIA can and cannot do is Executive Order 12036, put into effect by President Carter three years ago as an outgrowth of the Senate committee investigation.

A proposed revision of that order is curculating for comment within the itelligence community and is expected to be submitted soon to Reagan. A first draft of that proposal, leaked to the press in March, indicated that CIA was seeking authority to gather information on Americans at home, use intrusive techniques here and undertake intelligence operations in this country. CIA is supposed to be concerned only with overseas intelligence-gathering, with the FBI handling the domestic assignments.

Inman, in subsequent interviews, said that first draft was prepared by a working group and had not been endorsed by top leadership. He also said it was unlikely any such steps would be embodied in a new order. The new administration, Inman explained, had only asked the intellignece agencies to assess existing restrictions to see whether they impede effectiveness, especicially in dealing with terrorism or counterintelligence.

One CIA official said last week that the agency does not want a domestic surveillance role but would like to be able to assist the FBI, with the attorney general's permission, when the bureau requests some special technology available in CIA.

Aside from a new executive order, CIA officials say they are eager to have Congress enact legislation that would make it a crime to divulge the names of U.S. intellignece agents abroad and therefore "put out of business" newsletters that publish such names. Such legislation is pending in Congress.

In addition, a proposal to relieve CIA from responding to provisions of the Freedon of Information Act (FOIA) has been submitted to the administration. The concern here, officials say, is the impact on allied foreign intellignece agencies and hired undercover agents who can't conceive of an intelligence agency being forced to search its files and divulge information at the request of U.S. or foreign individuals. Though thus far the CIA has won every court case it has fought against certain FOIA requests, one official said "we can't control the judges and can't be sure we'll always win."

The CIA also is expected to recommend reconstructing the president's Foreign Intellignece Advisory Board, a group of seven to 12 senior and experienced civilian outsiders. This board was disbanded under Carter in favor of the three-member Intelligene Oversight Board. The reconstituted group, officials say, would have broader authority to look into CIA activities.

Aside from hiring Hugel and Stanley Sporkin, the former Securities and Exchange Commission staff official who is the CIA's general counsel, Casey has not engaged in any reorganization at the agency.

By most accounts, Casey's personal impact on morale inside the CIA is hard to measure, though things have perked up because of the generally more positive attitude of the new administration. Casey, CIA officials say, is the first director to be granted formal Cabinet rank. In comparison to former director Stansfield Turner, who did not have a standing invitation to Carter's top-level Friday morning breakfast meetings, Casey's proximity to the president ("I still call him Ronnie") assures the agency a high-level ear.

Officials say Casey, especially during the transition, continues to spend a great deal of time doing political chores and advising for the president. Casey was Reagan's campaign manager. Early in the new administration, he traveled to Japan, Saudi Arabia, France, West Germany and England. His aides say it was to familiarize himself with agency outposts. But others say he was carring messages from Reagan to leaders of those countries.

The new director also is seeking to improve analysis of intelligence collected by U.S. agencies. While that is a traditional goal, sources say Casey wants to get away, in at lest some intelligence estimate reports, from homogenizing various estimates into one consensus. He wants to provide a wider range of opinion to policy-makers.As officials explain it, Casey would give greater grominence to dissenting views, provided the dessenters can support their assessments.

Some officials, however, are skeptical, pointing out that top policy-makers usually don't have time to read two or three different estimates on the same issue -- they want a single, coordinated intelligence estimate. "After all," said one official, "that's what the director of central intelligence gets paid for."