Facebook will ban posts that deny or distort the Holocaust and will start directing people to authoritative sources if they search for information about the Nazi genocide.
CEO Mark Zuckerberg announced the new policy on Monday, in the company's latest attempt to take action against conspiracy theories and misinformation ahead of the US presidential election.
The decision comes amid a push by Holocaust survivors around the world, who led a campaign this summer that urged Zuckerberg to remove Holocaust denial posts from the social media site.
Coordinated by the Conference on Jewish Material Claims Against Germany, the #NoDenyingIt campaign posted a daily video on Facebook to encourage the removal of Holocaust-denying groups, pages, and posts.
Facebook said that the new policy "is supported by the well-documented rise in anti-Semitism globally and the alarming level of ignorance about the Holocaust, especially among young people.''
"For many years, we have worked with communities around the world to help us understand how hatred, including anti-Semitism, is expressed online."
Zuckerberg said in a blog post on Monday that he believes the new policy strikes the "right balance'' in drawing the lines between what is and isn't acceptable speech.
"I've struggled with the tension between standing for free expression and the harm caused by minimizing or denying the horror of the Holocaust,'' Zuckerberg wrote.
"My own thinking has evolved as I've seen data showing an increase in anti-Semitic violence, as have our wider policies on hate speech."
Zuckerberg caused controversy in 2018 when he suggested that Holocaust deniers were not "intentionally'' getting it wrong and that Facebook posts that were not calling for harm or violence would not be removed.
The Anti-Defamation League, a US-based Jewish NGO, said it was relieved by Monday's shift but criticised Facebook for taking nearly a decade to introduce the policy.
"While Facebook has made numerous positive changes to its policies since that time, it stubbornly had held onto this outrageous platform policy, even in the face of the undeniable threat of growing antisemitism and antisemitic violence around the world,'' the group's CEO Jonathan Greenblatt said in a statement.
The Claims Conference also welcomed the social network's decision to take action after its campaign sharing survivor testimonials.
"It's a very important statement and it's a building block toward ensuring that this sort of anti-Semitism is not amplified,'' said Greg Schneider, the group's executive vice president.
"Facebook is showing that it recognizes Holocaust denial for what it truly is - a form of antisemitism and therefore hate speech,'' Ronald Lauder, president of the World Jewish Congress, said in a prepared statement.
"Today’s announcement sends a strong message that Facebook will not allow its platform to be misused to promote hate."
But Facebook has warned that it could take some time to train the company's technical systems and human moderators to enforce the new policy on a global scale.