Gary Bartlam, 19, a member of the Royal Fusiliers, will appear before a court martial in Hohne, the regiment's base north of Hanover, Germany. The hearing is expected to last two days.
The courts martial of three other members of the regiment, Corporal Daniel Kenyon, and lance corporals Darren Larkin and Mark Cooley, will follow at nearby Osnabruck on Wednesday.
Bartlam was arrested in Britain in 2003 after staff at a photographic store in Staffordshire tipped off police about "trophy snaps" of the soldier's time in Iraq that he had asked them to develop.
The photos were reported to show acts of torture inflicted on Iraqi prisoners in a hangar in Basra in southern Iraq.
According to the British press, among the images was one of a detained Iraqi suspended in a net by a fork-lift truck then dropped to the floor.
"The Guardian and a number of other media organisations will
mount a legal challenge in the court today if the government attempts to prevent the details from becoming public"
Other pictures allegedly showed detainees forced into sexual acts on other prisoners and a soldier. None of the pictures have been published and the contents of the roll of film have not been officially confirmed.
In a statement to parliament last year, Britain's attorney-general, the government's top legal adviser, conceded that the charges against the troops "apparently involves making the victims engage in sexual activity between them".
Citing defence sources, the Guardian newspaper voiced fears that the media would be banned from divulging details of the charges, on the grounds that this might jeopardise the security of other soldiers operating in Iraq.
"The Guardian and a number of other media organisations will mount a legal challenge in the court today if the government attempts to prevent the details from becoming public," the paper said.