The conservative Heritage Foundation yesterday gave the Reagan administration its report card for the last 12 months. Judging by a 3,000-page blueprint for governance it published just after last year's election, it said the administration was scoring about 60 percent.

The first-year assessment was generous to the president himself, saying he had managed some remarkable successes for the conservative cause. But it complained that his designs had also been thwarted in many cases by failure to fill key jobs in a timely and orderly fashion and with true-believing appointees. For this it especially blamed the White House personnel office.

The foundation singled out as other particularly poor performers the Justice Department and Attorney General William French Smith, and the Defense Department.

The group's highest praise went to Vice President Bush's task force on regulatory reform, the Office of Management and Budget in its early days, the Department of Health and Human Services and Interior Secretary James G. Watt, a foundation alumnus.

Among the principal policy deficiencies cited in the report were a failure to close the so-called "window of strategic vulnerability" against the Soviet Union, failure to revoke executive orders requiring affirmative action by the government and government contractors in hiring minority-group members and women and failure to move more decisively toward abolishing the Energy Department.

The main successes cited include the speed with which the administration delivered an economic program to Congress, the turning back of federal programs to state and local levels, swift cutbacks in the broad HHS domain and an array of regulatory reforms.

The foundation's basis for judgment was its "Mandate for Leadership," a remarkably detailed work handed to the Reagan transition team 10 days after the 1980 election and which was on the local best seller list for three weeks. It contained some 2,000 policy recommendations designed to turn the government rightward as swiftly as possible.

Since its publication, at least three dozen of those who wrote or contributed to "Mandate" have switched from the stands to the playing field, accepting policy-making jobs in the administration. Among them are Interior's Watt; Norman B. Ture, undersecretary of the Treasury for tax policy, and Charles L. Heatherly, the editor of "Mandate," now at work in the Department of Education.

In its follow-up report, called "The First Year," the foundation says the administration has been "moving in the right direction" toward the broad conservative goals of reversing government expansion and strengthening the free enterprise system, national defense and individual liberties.

But, of the original 2,000 recommendations, the foundation felt 1,270 either could have been carried out or at least begun by now, according to its president, Edwin J. Feulner. "About 60 percent of those have been implemented or initiated," he said.

The foundation report places the heaviest blame for administration failures on personnel problems, a common thread from one agency to another.

"In almost every case, there were delayed appointments, unqualified or misqualified appointments or the appointment of individuals who are not committed to the president's goals and policies," it said.

Because of such problems, "regulatory reforms were delayed, legislative authority for some priority changes expired and the opposition was granted time to marshal its forces against important initiatives," the report said.

Of approximately 400 top officials in the executive departments and agencies, 55 percent had been announced, 36 percent had been nominated and only 21 percent had been confirmed by the beginning of May, 1981. Many of these positions have still not been filled and staff turnover in the executive branch has already begun, the foundation wrote.

In addition to administrative failures by E. Pendleton James' White House personnel office, the problem is compounded by the $50,112 pay cap on senior executives and the "unrealistic career and financial restraints" imposed by the Ethics in Government Act of 1978, which make it difficult to attract top job candidates, the report said. "Mandate" had called for reform of both of these.

The foundation gave special kudos to Anne M. Gorsuch, head of the Environmental Protection Agency, for her swift dismissal of subordinates who did not share administration policy views.

As for the president, although he has excercised effective personal leadership, the report finds, "the fact that he has been called upon so often to use his remarkable powers of persuasion is an indication of poor staff work." The Advanced Warning and Control System plane sale to Saudi Arabia controversy is one example given.

The report gives the aggressive OMB of last spring the highest marks of any agency it evaluated, "even exceeding the recommendations of 'Mandate.' " In addition to its speedy action in developing the budget and tax packages, the report praised the agency for "its willingness to regard all federal programs--including entitlements--as targets for budget cuts."

Here are other judgments in the report:

* The Justice Department, deemed a "major disappointment," not only has failed to implement most "Mandate" recommendations but has actively blocked reforms proposed by other departments. "Improvements are unlikely" because among other things, Attorney General Smith's top appointees "resemble a Wall Street law firm." These business lawyers, used to using junior aides for legal research, are ill-equipped to challenge staff attorneys who are well-versed on constitutional and policy issues.

This conflict is especially pronounced in the civil rights division, whose recent objectionable activities include challenging the constitutionality of a proposed legislative veto of agency regulations, entering into an agreement to stop using a federal employment exam which fails to produce a certain level of minority candidates and opposing regulations exempting colleges from some affirmative action regulations.

Still, the report praises Justice for its positions in favor of relaxing the Voting Rights Act and retreating on busing and the rights of illegal aliens.

* The Department of Defense has "fallen far short" of "Mandate" goals and in one key area--the "window of strategic vulnerability"--has acted in direct opposition. The administration "has not attempted to address these deficiencies in a timely or coherent fashion."

Among other Defense Department failures cited are the rejection of defensive basing for the MX missile, a bias in budget and planning toward general purpose forces to the detriment of more important weapons investment and failure to reevaluate the Rapid Deployment Force.

* The State Department, while notably improved over the "incoherence" of the Carter years, has been beset by both institutional and personality difficulties that have been a "nagging embarrassment." The administration could fix this if it would follow an original recommendation of "Mandate" to clarify the role of national security adviser Richard V. Allen. (The administration has followed the group's recommendation part of the way, in its move to make State its primary voice on foreign policy.)

Also, Secretary Alexander M. Haig Jr. has failed to fill many key positions with aides who share the Reagan philosophy.

On the other hand, the department has complied with "Mandate" proposals, for instance, in its reversal of President Carter's approach to some human rights issues.

* On energy issues, the Reagan administration has disappointed the foundation by taking only modest steps toward the "Mandate" recommendation that the Department of Energy be abolished. Meanwhile, the agency staff has resisted stated policies of the president and hindered efforts to reduce funding for "appropriate technology" and other programs.

The administration has also lagged in deregulating natural gas prices as fast as the foundation proposed and has failed to remove the responsibility for licensing nuclear exports from the Nuclear Regulatory Commission.

More pleasing to the conservatives was the administration's removal of price controls on crude oil.

* At Interior, Watt gets credit for shifting the previous balance away from preservation interests and back toward development.

* Federal education policy has followed "Mandate" recommendations for substantial change, transforming many categorical programs into block grants and moving toward abolishing the Department of Education. The revocation of regulations in this area "eliminated some 200,000 pages of grant applications, 7,000 pages of financial reports and 20,000 pages of program reports annually."

* The administration, led by Bush's task force, has used its administrative power effectively in pursuing regulatory objectives, centralizing the program within OMB. The report cites OMB reports that the daily length of the Federal Register declined 33 percent, the volume of proposed rule-making declined almost 50 percent and the federal paperwork burden was being substantially reduced.