The Pulp Fiction actress posted an emotional message online about the number of harassment and sex attack claims against the former producer.
She did not make any specific allegations but asked fans to “stay tuned”.
Uma, 47, said earlier this month she was too angry to talk about the once-powerful producer.
But this week she broke her silence in a Thanksgiving post on Instagram, praising those who have the “courage” to stand up for those in need.
She included the “Me too” hashtag – the social media phenomenon which saw women worldwide share their experiences of sexual harassment.
Uma wrote: “I am grateful today, to be alive, for all those I love, and for all those who have the courage to stand up for others. I said I was angry recently, and I have a few reasons, hashtag ‘me too,’ in case you couldn’t tell by the look on my face.
“I feel it’s important to take your time, be fair, be exact, so…Happy Thanksgiving Everyone! (Except you Harvey, and all your wicked conspirators – I’m glad it’s going slowly – you don’t deserve a bullet) – stay tuned.”
Alongside the message, Uma posted a photograph of her character in Kill Bill, who vows to go on a “rampage of revenge.”
A flood of allegations have emerged in the wake of the scandal engulfing the film producer, 65.
He faces accusations of sexual assault from scores of stars including Angelina Jolie, Rose McGowan, Gwyneth Paltrow and Cara Delevingne.
The former executive denies engaging in “non-consensual sexual conduct.”
Uma has made several movies produced by Weinstein, including Pulp Fiction and Kill Bill.
When she was previously asked how she felt about women speaking out about their experiences of harassment, she replied: “I think it’s commendable.
“I have learned, I am not a child and I have learned that…when I’ve spoken in anger, I usually regret the way I express myself. So I’ve been waiting to feel less angry. And when I’m ready, I’ll say…