Hollywood actors Robert de Niro and Alec Baldwin, Oscar-winning director Michael Moore and singer Cher were among those who joined the noisy gathering close to the Trump International Hotel on Central Park South.
A crowd of several thousand people thronged Columbus Circle and Central Park West, the boulevard outside the five-star hotel.
"Fight Trump every day" and "justice and civil rights for all," read placards at the rally in the president-elect's hometown, where a majority of people voted for his Democratic rival Hillary Clinton in last year's election.
Baldwin, who lampoons Trump in a regular slot on comedy TV show "Saturday Night Live" to rave reviews and repeated Twitter drubbings from the thin-skinned Republican billionaire, took to the podium to do his Trump impression.
"Are we going to have 100 days of resistance?" he said, revving up the crowd and switching to his regular voice. "Fantastic!" he hollered.
"He does not rule with a mandate," Moore said in reference to Clinton's win of the popular vote and Americans who voted for independent candidates.
"We are the majority. Don't give up. I won't give up," he said.
Mayor Bill de Blasio, a Democrat, issued a rallying cry for progressive politics and urged Americans across the country to rise up and make their objections to the incoming administration heard.
"Donald Trump always liked to say he built a movement, well now it's time for us to build our movement and that starts tonight and it's all over the country, tonight, tomorrow and in the days to come," de Blasio said.
He championed universal healthcare, protecting the world from climate change and preserving rights gained under the outgoing Barack Obama administration.
"Look at the thousands here tonight and that is only the beginning," he added.
A poll released by Quinnipiac University said 46 percent of New York voters want to mayor to try to get along with the president-elect while 45 percent believe he should be a national leader against Trump's policies.
Graphic designer Patrick Mavros, a member of the crowd, said it was a demonstration against the Trump administration and what his cabinet -- predominantly white, wealthy and male -- stands for.
"Anywhere from LGBT rights to women's rights to Muslim rights. I think it's a symbol that people will not be standing idly and let them get away with what they want. We will be watching and hold them accountable," he told AFP.
"We are here because we feel we're going to lose all these gains from the past 50 years -- civil rights, freedom of speech, healthcare, women's rights, world peace, you name it," said Carol Bay, a therapist attending with her wife.
"We're going to lose it all because they've been asking to take them back for all these years," she said in reference to Republicans.
