Moussaoui made a 50-minute address
"I pray for the destruction of the United States of America," he said, during a 50-minute address to a court in Virginia.
US District Judge Leonie Brinkema has ordered a psychiatric evaluation to decide whether Mr Moussaoui, 33, is capable of defending himself against charges on which US prosecutors are seeking the death penalty.
Mr Moussaoui, a French citizen of Moroccan descent, is accused of conspiring with Osama Bin Laden, the hijackers and others to commit the attacks on the US.
Prosecutors believe he was meant to be the 20th hijacker and he is the only person charged over the 11 September attacks.
The plane that crashed into a Pennsylvania field only had four hijackers on board, while the other three planes carried five.
The trial is due to begin on in October.
'Evil money'
Mr Moussaoui told the hearing that the case against him was "a sophisticated version of the kiss of death.
"They only need me for the gas chamber," he said.
Judge Brinkema warned him that US law was extremely complicated.
Mr Moussaoui also said that he wanted a trial without a jury, accusing the US Government of "spending millions of their evil money to kill me".
He described the judge as "a field general entrusted to get this matter over quickly".
Last week, lawyers appointed to represent him asked for improved jail conditions for Mr Moussaoui.
He is being held in near-isolation, kept in his cell for up to 22 hours a day, at a detention facility in Alexandria, Virginia.
His lawyers say he needs a computer to help him prepare for his trial.
No plea entered
Mr Moussaoui faces six charges of conspiracy, including conspiracy to destroy aircraft, to murder US citizens and to use weapons of mass destruction.
Court papers accuse Mr Moussaoui of having been "intentionally and specifically engaged in an act of violence, knowing that the act created a grave risk of death".
Prosecutors have said Mr Moussaoui's actions resulted in the deaths of about 3,000 people, the largest loss of life stemming from a criminal act in US history.
They added he "has demonstrated a lack of remorse for his criminal conduct".
Mr Moussaoui was detained in mid-August last year, after arousing suspicions while seeking flight training in Minnesota.
Appearing in federal court in January, Mr Moussaoui refused to enter a plea.
The court entered a not guilty plea on his behalf.