The soldier, operating with The Light Dragoons Battle Group, died as a result of a gunshot wound he sustained whilst on a foot patrol in the Babaji district, central Helmand province.
Spokesman for Task Force Helmand, Lieutenant Colonel Nick Richardson, said:
"This brave soldier died bringing a better life to the people of Afghanistan. We mourn his loss and our thoughts and prayers are with his family, friends and colleagues at this time. His loss has not been in vain."
Next of kin have been informed and have asked for a period of grace before further details are released.