The US President said the soldiers, who were taken to hospitals after the attack earlier this month, did not have serious injuries "relative to other injuries I've seen".
During a televised speech following the missile strike, Mr Trump had claimed: "No Americans were harmed in last night’s attack by the Iranian regime.” It later emerged that 11 had been injured.
Speaking to reporters at a press conference in Davos, Switzerland, on Wednesday, Mr Trump said: "I heard that they had headaches, and a couple of other things, but I would say, and I can report, it is not very serious."
He added: "I don’t consider them very serious injuries relative to other injuries that I’ve seen.
"I’ve seen what Iran has done with their roadside bombs to our troops… I’ve seen people that were horribly, horribly injured in that area, in that war.
Referring to the soldiers who were taken for treatment last week, he added: "No, I do not consider that to be bad injuries, no."
When asked about the 11 U.S. servicemen injured in the Iran airstrikes, President Trump told @weijia he didn't "consider them serious injuries relative to other injuries I've seen." https://t.co/anmIdCHO6a pic.twitter.com/boSjvDujCS— CBS News (@CBSNews)January 22, 2020
One Twitter user responded by saying: "Tell that to their families. While casualties were expected, this attempt diminish the gravity of it, by president of United States of America is alarming.
"For anyone suffering a TBI (Traumatic Brain Injury), it is NO SMALL MATTER. TBI can be a life changer. Worse, it is invisible injury, with no cure."
The Iranian air strikes came as a direct response to a US drone strike that killed the general Qasem Soleimani.
Tensions remain between the two countries, but they have since appeared to step back from the brink of military conflict.