Alexandre de Moraes ordered the immediate and complete suspension of the social media platform until it complies with all court orders and pays existing fines.
The row began in April, with the judge ordering the suspension of dozens of X accounts for allegedly spreading disinformation.
Reacting to the decision, X owner Elon Musk said free speech is the bedrock of democracy and an unelected pseudo-judge in Brazil is destroying it for political purposes.
By Saturday morning some users had reported access to the platform was no longer possible.
It closed its office in Brazil earlier this month, saying its representative had been threatened with arrest if she did not comply with orders it described as censorship – as well as illegal under Brazilian law.
Justice Moraes had ordered that X accounts accused of spreading disinformation – many supporters of the former right-wing president Jair Bolsonaro – must be blocked while they are under investigation.
He said the company’s legal representatives would be held liable if any accounts were reactivated.
The head of Brazil’s telecommunications agency, which has been tasked with suspending the platform, said he is proceeding with the compliance to do so.
Justice Moraes has given companies such as Apple and Google a five-day deadline to remove X from its application stores and block its use on iOS and Android systems.
He added that people or businesses using means such as VPNs -virtual private network- to access the platform could be fined £6,700.
According to the judge’s order, a ban will be in effect until X names a new legal representative in the country and pays fines for violating Brazilian law.