Of the 12 new arrivals, six Marines and two soldiers had combat-related wounds, described as mostly "blast injuries," said the medical center's director, Maj. Dr. Yong Chun.
Of those injured in battle, two were in the intensive care unit in stable condition and four were in medical surgical wards, Chun said.
Medical personnel would not discuss the circumstances of the casualties.
The 12 arrived at Landstuhl after being flown into nearby Ramstein Air Base on Monday.
They were carried off a C-141 cargo plane by stretcher and placed onto waiting medevac buses, which took them to Landstuhl.
None of the wounded at Landstuhl is from the 101st Airborne Division, said Capt. Norris Jones, spokesman for European Command.
The 101st's camp in Kuwait was the scene of a grenade attack Sunday by a U.S. soldier who wounded 15 of his fellow soldiers, three of them seriously.
Casualties from the 101st are expected to arrive within 48 hours, Jones said. He was unable to say how many casualties would come in from the 101st and was unable to describe their injuries.
The two wounded Marines who arrived Sunday marked the first patients at Landstuhl from the Iraq war.
They joined some 2,000 patients who have come to the medical center since October 2001, when the hospital received its first troops from Operation Enduring Freedom in Afghanistan, said Col. David Rubenstein, the medical center's commander.
Landstuhl receives patients from mobile army hospitals and field hospitals and provides further stabilization to prepare them for rehabilitative care or return to duty.