The attack on Friday in Balad, 75 kms north of Baghdad, occurred at about 5:00 pm (14:00 GMT) and the soldier was killed from shrapnel, said Sergeant Robert Cargie, a spokesman for the 4th Infantry Division.
He said troops searched vehicles in the area after the attack and have detained six suspects, adding that the wounded soldiers were in stable condition.
The latest death brings to 213 the number of the US combat
casualties since US President George Bush declared an end to hostilities in Iraq on 1 May.
On Friday, one US soldier was killed and another injured when insurgents shot down a reconnaissance helicopter in the volatile town of Fallujah, west of Baghdad.
Night of terror
Relative calm returned to Baghdad on Saturday morning after a night of heavy artillery and cannon fire in Iraq's war-torn capital.
US aircraft roared overhead and deafening bangs shook the capital throughout the night as occupation forces continued their week-old crackdown against resistance fighters.
"That is a continuation of the ongoing Operation Iron Grip," a US military spokesman said of the bombardment which started at around 10:20 pm (1920 GMT) on Friday night.
Iron Grip, launched on 24 December, has targeted fighters' hideouts used for firing mortars on the US-led occupation fortress-like headquarters on the west bank of the Tigris.
The US offensive has primarily been on the outskirts of Baghdad in the southern suburb of Dura.
According to an Aljazeera correspondent in Baghdad, the attack lasted for three hours. Witnesses said two mortar bombs were also dropped on a house in al-Yarmouk district.
"Citizens in Baghdad are now suffering from a power cut and shortage of fuel," the correspondent added.