Wesam al-Delaema was put on a plane and flown to an undisclosed location in the US after losing his final appeal against extradition in December.
He is set to become the first suspect tried in a US court for allegedly plotting attacks on US forces in Iraq.
Mr Delaema denies charges of "possessing a destructive device".
Authorities say the evidence against him includes a videotape he made of Iraqi insurgents preparing a roadside bomb.
In Dutch court hearings, he argued that he was kidnapped and forced to make the video on pain of death.
Mr Delaema was arrested in May 2005 in the Dutch city of Amersfoort in following a tip from US authorities.
His lawyers have argued that the US has no right to try him. They say they fear he could be tortured and will not get a fair trial.
But a Dutch judge said there was "no reason to believe that the US authorities will not abide by the commitments they have given or... deprive the suspect of his fundamental rights".
The US has given assurances that he will be tried in a federal court, not by a military commission, and can serve any sentence in the Netherlands.
The charges carry a maximum sentence of life in prison.
A Dutch justice ministry spokesman said on Saturday that Mr Delaema was on his way to somewhere in the US.
"Even if I knew where he is headed, I couldn't say," he said. "It's a matter for the US justice department now."