The company said Kurt Fenech, known online as Kurt0411, had posted "abusive and threatening messages" about its employees.
It said it had banned his account and blocked his console from accessing its games.
Mr Fenech denied making abusive remarks and told the BBC he thought the ban was an "abuse of power".
The gamer has more than 100,000 subscribers on YouTube and often attracted more than 10,000 viewers to his live streams of the Fifa 20 football video game.
