Mohiussunnath Choudhury, 26, is accused of "engaging in conduct in preparation for giving effect to his intention to commit an act or acts of terrorism", Scotland Yard said in a statement.
Choudhury, from Luton, north of London, was arrested outside the palace gates on Friday.
Three police officers suffered minor injuries after he allegedly drove a car at officers outside Buckingham Palace and then reached for a four-foot (1.2-metre) long sword.
He was charged with an offence contrary to the Terrorism Act 2006 and was due to appear in custody at London's Westminster Magistrates Court later Thursday.
