Greg is set to take to the airwaves with his daily drivetime programme from Camp Bastion in Helmand Province for five days beginning on Monday December 10.
All week he will deliver Christmas messages and music dedications from the UK and back from Afghanistan - linking troops with their friends and families at home.
Teaming up with British Forces Broadcasting Service (BFBS), the stint with the troops follows on from last year when Tim Westwood broadcast for BBC Radio 1 and BBC Radio 1Xtra.
Speaking about his week in Afghanistan, Greg said: "I'm really excited to be bringing Radio 1 out to the troops and show them how much we appreciate their hard work.
"I love a challenge and an adventure and this will be a brilliant opportunity to see how BFBS and Camp Bastion works.
Rhys Hughes, Head of Programmes for BBC Radio 1 and BBC Radio 1Xtra, said: "Our ambition is that BBC Radio 1 with Greg James will reflect what it feels like for our armed forces personnel to live and work in Camp Bastion.
"We are delighted to be returning to Camp Bastion for a third year, working very closely with our friends at BFBS to connect Service personnel with their families back in the UK and around the world."