American feminist Kate Millet yesterday ran into her stiffest opposition since arriving here a week ago. Paradoxically, the trouble came from some of the embattled Iranian women she's here to help in their fight for equality.

At a news conference Millet organized to introduce her Iranian feminist friends, women hecklers contested their credentials and right to speak in the name of Iranian women.

The often confused proceedings were suffused with an underlying hostility. It appeared directed ore toward Millet's thesis of international feminist solidarity than her presence here as a foreigner -- and a suspect American at that -- in these xenophobic post-revolutionary times.

Democratically, she asked the hecklers to join her and her friends at the speakers' table, but they declined.

Talking out problems -- and the techniques of consciousness-raising -- have not caught on in Iran, where many of the Western-educated women leaders are split among orthodox communist, Maoist democratic and Trotskyite tendencies.

Particularly upsetting to the hecklers was Millet's insistence that Shah Mohamed Reza Pahlavi had done nothing for Iranian women -- an assertion that the dissenters, although no friends of the departed monarch, felt flew in the face of reason.

But Millet drew no rejoinder in asserting that because of the threat of Islamic fundamentalism, "our rights of education, abortion, child-care, divorce, employment in the professions -- all the things we have fought for since the commencement of the women's movement in 1847 -- are in great jeopardy in this society."

Earlier in private conversation Millet, the author of "Sexual Politics," had denounced the general atmosphere: "It is not only the women who are fed up, but vast numbers of people, about the abrogation of civil justice, the executions, the puritanism, the general joylessness, the narrow ecclesiastical and antidemocratic tone."

"Women," she asserted, "will lead the protest in Iran against all curtailment of democracy and constitutional freedom."

Active for seven years in the United States with the anti-shah Committee for Artistic and Intellectual Freedom in Iran, Millet was invited here by Iranian friends for International Women's Day.

It coincided with a massive women's demonstration against Islamic fundamentalist attempts to force women to wear full-length chadors and accept second-class status.

Although obviously a foreigner, Millet said that "Not one person has said this is none of my business or that this is not my country."

"I've never looked at a situation this tough," she said. "This is the first time as a pacifist and a feminist I've had to face guns."

"All those young men with guns they hardly known how to handle," she added. "Never before had I seen whole columns of youths shaking their fists. No, I didn't expect so much overt hostility from men. This is quite new -- the overt, physical, masculine threat."

As well-traveled as Millet is, she said, "I saw two things which astonished me when I got off the plane in Tehran.

"There was a wall of women in chadors. It was enormously dramatic and beautiful -- a kind of theater. I think the chador is a beautiful garment if you wear it by choice, rather than forced on pain of being spat on or stoned or threatened with one's life. It's a bit like long skirts -- I love to wear them, but you can't do any work in a chador or carry anything and that veil is telling you you are no one. Physically, it's like bound feet."

The other thing she noticed was "the guns -- then I realized I was here. A naked carbine is as oppressive as hell. In one second my eyes swept the wall of black figures and right behind them was a gun in the hands of a very nervous youth, his finger on the trigger."

Sipping on a whishkey -- a luxury in this increasingly teetotal town -- Millet insisted that "Iranian women who fought and died and risked their lives against tanks are furious to see their hopes threatened and the uprising they aspired to be a revolution betrayed."

As for Ayatollah Ruhollah Khomeini, the unofficial chief of state, who now leads the fundamentalist Islamic movement, she said, "He talked differently in Paris" when he was still in exile.

"He's probably given in to the hierarchy, and has around him his college of cardinals," said the former convent student. "He was courageous against the shah, but he has become narrow-minded and anti-democratic."

At the news conference, Millet ws asked if she considered it germane to call Khomeini a "male chauvinist pig." She replied: "Male chauvinist pig would be a simple, idiotic way of defining him, but it would be germane."

What can she or anyone else do?

"All the women of the world are looking to Iran -- this is the hardest place in the hardest Islamic culture. We will provide the liaison with our Iranian sisters. The struggle will not be easy and often it will be dangerous. But now there's at least a chance."