As close associates tell it, U.N. Ambassador Jeane J. Kirkpatrick has been saying privately she does not like her job very much. The United Nations, she has told friends recently, is a wearying place where criticism of the United States is steady and harsh, where traditional allies rarely support this nation and where social obligations are unrelenting.

And, it is said, she has been unhappy about some of the things her bosses in the Reagan administration have done. These include selling better planes to Saudi Arabia than to Taiwan, not resisting communist subversion in Central America vigorously enough and not acting forcefully enough in opposition to Polish martial law.

"I would say that those comments are all true, but they are only partial truths," the 55-year-old former Georgetown political science professor said during an interview as she completed her first year as ambassador.

"They are the kind of comments that I might make about teaching at the point when I was grading exams or term papers. I love teaching but I never liked grading exams or term papers and what those comments do is focus on aspects of this job in moments of exasperation," she said.

Actually, this "is a helluva job. . . simultaneously fascinating, frustrating, infuriating, tiring and worth doing. That's what I really think about the job," she said, adding that she thought she had done her job reasonably well in this first year and that "in the second year I will be able to do it better."

In recent weeks, there have been press reports that Kirkpatrick had intended to resign because of unhappiness over the administration response to the Polish situation but was talked out of it by the White House.

"I didn't threaten to resign," she says, "and I don't propose to resign. It is very important for me to be a disciplined, loyal member of any team that I play on. I would never engage in . . . publicly undercutting . . . policies of the government of which I am a part and it is for that reason that it is terribly painful and inappropriate" to have reports of her "purported" views surface, she said.

Her closest associates confirm that, while they have heard complaints, they never heard her actually threaten to quit. It is known, however, that she was especially upset by the contrast between the quick and harsh administration denunciation of Israel for announcing annexation of the Golan Heights and the relatively mild initial reaction to the Polish crackdown.

Kirkpatrick, her associates say, was also dismayed by the way the administration quickly turned its attention to the Soviet Union as the culprit rather than carrying out a more focused campaign aimed at Polish authorities.

Within the administration, Kirkpatrick attends meetings here of the Cabinet, the National Security Council and the Special Situation Group, the crisis management group headed by Vice President George Bush. She gets high marks from within the administration for "very effective, useful opinions, expressed well" in such councils, senior officials say.

Kirkpatrick, a Democrat whose conservative foreign policy views and ability to express them caught Ronald Reagan's attention, says that despite her years of studying and writing about diplomacy, the United Nations "has been a colossal learning experience."

The influence of the United States in the United Nations on everything from the agenda to the outcome of votes is even less than she imagined it to be, she says. "We are really quite isolated. I believe it is the case that we have many good friends and no reliable allies," she goes on, in trying to explain why the United States so often is alone.

That is by no means a new phenomenon, Kirkpatrick says. It goes back through many administrations. The U.N. for many years now has been dominated by blocs of so-called nonaligned countries, or Soviet or Arab or African blocs, many of them interlocking and with views sharply different from Washington's.

But she believes it is even worse now because even America's "best friends" in Western Europe, members of the NATO alliance, have "developed a habit of voting together on almost all issues" as members of a European bloc of 10. Their positions usually represent the easiest possible "consensus" and are "often different from the U.S. position."

The most dramatic example came in the recently completed General Assembly session when only Britain abstained, while all nine other European allies voted for a resolution on El Salvador that the Reagan administration strongly opposed.

"Our views of the world are not the dominant ones at the U.N., that's for sure," she says. "Israel is a very unpopular nation at the U.N. and our position of support on Israel and the Middle East is a very unpopular one. Israel is regularly scapegoated in the U.N. The Arab bloc is very well organized, sometimes linked to the Soviet bloc on one hand and the Africans on the other. The phrase 'zionism is racism' embodies the political alliance between Arabs and Africans on Middle East as well as African questions," she says.

On human rights, Kirkpatrick says, "We have argued for a single standard, a desire to judge Chile by the same standards as Cuba and treat them in comparable ways," and "that's not a popular position," either.

The double standard, she believes, also applies to South Africa, which can become "an instant object" of a Security Council censure for a foray into Angola "while Libya can invade and occupy the whole of Chad without ever having a resolution or action of any kind brought against it in the U.N.

"We are in a situation in which on almost every issue we lose. The biggest question becomes how we are going to lose," she says. "How long is it going to take . . . will we lose big or small? That's a very frustrating situation to be in."

The steady beat of criticism aimed at the United States in the U.N. and the high "level of invective" generally on many issues are some of the things that take a toll on the ambassador.

Kirkpatrick, however, has also followed the pattern of former U.S. ambassador to the U.N. Daniel Patrick Moynihan in "making a deliberate decision to answer attacks." That, too, Kirkpatrick explains, is "kind of a violation of the dominant U.N. political culture" that foreign diplomats view as a mistake. "But we believe it is something we need to do whether it is appreciated or not."

Kirkpatrick stunned scores of delegations last fall when she wrote letters sharply rebuking nations for associating themselves with a Cuban-engineered communique containing "malicious attacks" on the United States. But Kirkpatrick says the letter was only the most visible part of a strategy in which the United States is now trying to counter the U.N. political culture and which, she believes, is having some success despite all the built-in problems.

Congressional action that came on top of her letter, essentially a threat to cut foreign aid to countries that continue to associate themselves with that nonaligned communique, is viewed as especially important. Also, Kirkpatrick believes that her mission at the U.N. has done an especially good job at cultivating Latin American contacts.

The U.S. strategy is also to work harder in national capitals. The idea is to get countries that otherwise have reasonable relations and economic ties to the United States to have their delegations in the U.N. reflect those realities. Now many countries vote against the United States in the comfort of blocs and then "come around and say 'you know we really didn't mean it,' " as Kirkpatrick puts it.

She believes that U.S. administrations generally have not focused on this crucial difference between multilateral and bilateral diplomacy. "We have been very careless about this . . . and I think that is how we arrived at our low state" of influence in the U.N., she adds.

The Carter administration's U.N. ambassadors, Andrew Young and Donald McHenry, "had a much more clear-cut, heavier focus on Africa," Kirkpatrick says. "I would like to think our focus is more worldwide without being less African. I think they represented the policies of their administration and I do my best to represent the policies of our administration."

On the wall in the lobby of the U.S. mission in New York, a plaque honoring previous U.N. ambassadors shows that since the years of Henry Cabot Lodge, Adlai Stevenson and Arthur Goldberg between 1953 and 1968, the average stay of an ambassador has been well below two years. "I suspect that has more to do with wear and tear than anything else," Kirkpatrick says.

"I will tell you, however, that I will not quit this job because I find it frustrating or because I just got tired. And the reason I won't is because I have some terribly serious views about U.S. foreign policy and the American role." Only if it gets to the point, she says, where there is no longer a reasonable possibility that she can make a positive contribution to that policy, will she step aside.

Would she serve beyond two years? "No comment," she says.