United Nations, N.Y. — As Jeane Kirkpatrick prepares to leave her post as United Nations ambassador early next year, her record is being hotly debated among diplomats here. She clearly enjoyed the strong support of many of her fellow Americans and built herself a solid constituency among conservatives around the country during her four years as United States permanent representative to the UN. But she also became one of the most unpopular diplomats in the history of the United Nations.
Was she effective?
''It is too early to tell, the dust will have to settle first. Seen at this very moment, the performance appears to have been a mixed bag,'' says one of the few UN diplomats who has managed to remain emotionally detached when analyzing Mrs. Kirkpatrick's role.
''From the beginning,'' says one Western diplomat, ''she has been a controversial figure. She had some ardent supporters. She was also deeply disliked by many others. When all is said, her problem at the UN was not so much the substance of her policies as her personal style.''
Many high-ranking diplomats from the industrial nations and from the third world share this assessment and are willing to comment on her, on the condition that they remain anonymous.
One senior diplomat from a NATO ally lists her pluses:
* ''She stood up to the Russians. She scored propaganda points when defending Western values and denouncing the hypocrisy of America's enemies.
* ''She managed to mute the verbal abuse to which the West and the US had been submitted in the past by third-world representatives. Indeed the current General Assembly is the most moderate that one has watched in years.
* ''She has been coherent, articulate, firm, and honest in expressing the views of an unrepentant neoconservative, a believer in Teddy Roosevelt's approach to foreign affairs.
* ''By strengthening the moderates and weakening the radicals, she has made the UN more effective, more responsible, and more credible.
* ''She has scored a few resounding victories: recent attempts to expel Israel from the UN were easily defeated and a Cuban attempt to raise 'the question of Puerto Rico's right to independence' was also repelled. Furthermore, she was instrumental in restraining the growth of UN finances.
* ''She developed a good working relationship with UN Secretary-General Javier Perez de Cuellar.
* ''She had clout since she had the ear of the President.
* ''She was a staunch defender of Israel and vetoed all the resolutions condemning the West Bank settlements. One Israeli diplomat once said that 'She was the best representative Israel ever had.'
* ''Her colorful style, her combative speeches put the UN in the limelight.''
One nonaligned diplomat lists her minuses:
* ''By being haughty, snotty, abrasive, she rubbed many people, including loyal friends of the US, the wrong way. She could have made many of her points differently, without patronizing or threatening. She snubbed many excellent diplomats without good reason. . . Daniel Patrick Moynihan had been equally tough ideologically, but he was popular because he treated people with respect.
* ''She tended to constantly lecture people. European, Asian, Latin American ambassadors are not high school graduates. Furthermore, they know that she is not a top-notch academic such as Henry Kissinger, Stanley Hoffmann, and Seweryn Bialer. Her expertise on Latin America was seriously challenged by leading Latin American diplomats who found her knowledge gaps 'astounding.'
* ''She lost as many battles as she won. For instance, she was not able to block Guyana's and Nicaragua's election to the Security Council in '81 and '82. Or to stop the Law of the Sea Treaty, opposed by the US government, from being adopted.
* ''She made the UN her whipping boy. 'The UN is against us,' she once proclaimed and she lambasted the UN in many of her speeches. Indeed she managed to gag the UN, but only by seriously weakening it.
* ''Her strong arm tactics may in the long run backfire. By drawing scoreboards of voting patterns of neutral and nonaligned nations and reprimanding them for not being sufficiently pro-American, by threatening to cut off aid to poor and sometimes starving third-world countries, she may have improved the position of the US in UN ballots in the short run, but may have created deep-seated animosities vis-a-vis the United States. She made the US look like a big bully . . .
* ''The greater moderation displayed here recently by many third-world countries may be attributed to her brand of diplomacy only in part. In times of recession the needy, the dependent, tend to be less strident. The new cold war waged in recent years between the two superpowers drove many third-world countries to seek shelter behind the US and the USSR.
* ''She spent more time in Washington sitting in on National Security Council meetings and abroad making speeches than minding her UN store.
* ''She often acted as a loose cannon. Her disagreements with (former) Secretary (of State Alexander) Haig and more recently with Secretary (George) Shultz provided observers here with spicy episodes but did not really add to the good name of US diplomacy.''
Two dozen diplomats (Israeli, South African, Central American, West European) spoken to by this correspondent give her ''very good marks.'' Many others say ''good riddance'' with reference to her departure.
One UN official believes that, in all fairness, ''it is too early to judge whether she has strengthened or weakened the UN, improved the position of the US or isolated it. It may take years to seriously assess her performance and to allow us to pass judgment on it.''