Better contingency planning for the treatment of seriously injured servicemen and women is needed, the Public Accounts Committee has warned.
Most seriously injured troops are taken to Selly Oak Hospital in Birmingham after their return to the UK. They are then often moved to Headley Court in Surrey for rehabilitation.
The committee praised the treatment provided in recent years, saying that soldiers are surviving now who would have died in previous wars. Some 565 service personnel have been seriously injured in Afghanistan and Iraq since October 2001.
But the committee said it is concerned that there is only a voluntary agreement with the NHS that soldiers would be taken to other West Midlands hospitals if Selly Oak is full.
It also urged that the "military culture" at Selly Oak would need to be transferred to any new sites for soldiers.
"Injured military personnel should be treated in a military environment which is suitable for their needs. If Selly Oak remains under pressure for more than five days there are arrangements for military patients to be treated in other hospitals across the UK, but these arrangements need strengthening."
It added that the Ministry of Defence needs a "more robust" plan detailing which NHS hospitals military patients would go to, and how it would replicate elsewhere Selly Oak's expertise and experience with serious battlefield injuries.
The report followed confirmation a British soldier killed by a grenade in Afghanistan on Friday had earlier survived a controversial US "friendly fire" attack in Iraq.
Lance Corporal of Horse Jonathan Woodgate walked away from the 2003 incident which claimed the life of his colleague Matty Hull. L/Cpl Woodgate received holes in his bulletproof vest but was otherwise unscathed.
L/Cpl Woodgate, who was born in Bury St Edmunds, Suffolk, was killed in Sangin, Helmand province, while carrying out what was due to be his last patrol of his current tour when a grenade was thrown from behind a wall.