Facebook has removed the official page of far-right group Britain First, along with those of party leader Paul Golding and deputy leader Jayda Fransen.
The social network said it had taken action after they repeatedly broke the site's community standards on hate speech.
Mr Golding and Ms Fransen were jailed earlier this month after being convicted of religiously-aggravated harassment in Kent last year.
Facebook said they had continued to violate its rules despite issuing written final warnings over their conduct.
"Content posted on the Britain First Facebook page and the pages of party leaders Paul Golding and Jayda Fransen has repeatedly broken our Community Standards," Facebook said.
"We recently gave the administrators of the pages a written final warning, and they have continued to post content that violates our Community Standards.
"As a result, in accordance with our policies, we have now removed the official Britain First Facebook page and the pages of the two leaders with immediate effect.
"We do not do this lightly, but they have repeatedly posted content designed to incite animosity and hatred against minority groups, which disqualifies the Pages from our service."
Facebook confirmed the violating content included an image of the group's leaders with the caption 'Islamophobic and Proud' and multiple videos that Facebook said had been posted deliberately to incite hateful comments against Muslims.
The social network also confirmed that the group will not be allowed to set up an official Facebook page in the future.
When questioned by MPs at the end of last year, Facebook policy head Simon Milner told the House of Commons Home Affairs Select Committee that Facebook was "reviewing" the group's page after other social networks, such as Twitter and YouTube, suspended group accounts.
In response to questions over why the group had remained on the site, Mr Milner said Britain First had until recently been registered with the Electoral Commission and therefore "deemed legitimate" by the authorities, but there were "clearly issues" with the page.
He said the site was "very cautious" about political speech, and in Facebook's statement on the page removal, the company reiterated its stance.
"We are an open platform for all ideas and political speech goes to the heart of free expression. But political views can and should be expressed without hate," the social network said.
"People can express robust and controversial opinions without needing to denigrate others on the basis of who they are."
Following its suspension from Twitter in December, Mr Golding said the group was looking for new social networks to join and urged supporters to follow.