The soldier was killed while on an operation in the Nahr-e Saraj (South) district of Helmand province to recover a cache of improvised explosive device components that had been discovered the previous evening.
He was escorting a specialist team to the cache to remove these components when he was caught in an explosion from another device, a short distance away from the original find.
Spokesman for Task Force Helmand, Lieutenant Colonel Tim Purbrick, said:
"It is with much regret that I have to inform you of the death of a soldier from 1st Battalion The Rifles near Jamal Kalay in the Nahr-e Saraj district of Helmand province. The soldier was part of a foot patrol which had been deployed to assist with the recovery of a cache of improvised explosive device components.
"As he led the specialist Counter-Improvised Explosive Device Team to rendezvous with another patrol at the start of the operation, the soldier was fatally injured in an explosion. Our thoughts and prayers are with his family and friends."
The serviceman's next of kin have been informed and have asked for a period of grace before further details are released.