Watson is playing the lead role in The Circle, the film adaptation of Dave Eggers's novel about an all-seeing tech corporation.
She plays a graduate who joins Hanks's company and soon finds herself joining an experiment that pushes the boundaries of privacy and ethics.
Watson said at the New York premiere: "For my sanity, I cannot, I just cannot even go there (reading comments)."
"I have to create some distance because I'm human. I think there's this way where technology can dehumanise."
She's not the only celebrity who has had issues with social media in recent years:
Singer Ed Sheeran announced he was "taking a break" from social media in 2015 - not because of trolls but because he was "seeing the world through a screen and not my eyes".
Writing on his Instagram account, the singer explained he was "taking the opportunity of not having to be anywhere... to travel the world".
Ed returned to the social media universe exactly a year later, tweeting just an image of a blue square.
Back in 2015 Adele told the BBC she doesn't have direct access to her official Twitter account.
"I'm not a drinker any more, but when Twitter first came out I was, like, drunk tweeting, and nearly put my foot in it quite a few times," she explained.
"So my management decided that you have to go through two people and then it has to be signed off by someone, but they're all my tweets.
"No-one writes my tweets. They just post them for me."
But on the Brisbane leg of the tour she revealed how she gets around it.
"I'm not allowed access to my own Twitter because I'm quite mouthy and I say the wrong thing a lot of the time. So they took that privilege away from me."
The Harry Potter creator has turned the table on the trolls - she's become famous for her Twitter takedowns.
Following her criticism of Donald Trump last year, one Twitter user said they would now "burn your books and movies, too".
To which JK responded: "Well, the fumes from the DVDs might be toxic and I've still got your money, so by all means borrow my lighter."
Singer James Blunt is also a fan of the troll put-down.
One of his corkers pointed to the fact that while some may not like his music or appearance, he was sitting pretty on top of a very healthy bank balance.
Along with this self-deprecating gem: "Yup, it's called "Greatest Hit" in response to a tweet which asked: "There's a "best of" James Blunt? Really?"