The single strand, which is displayed in the middle of a record and framed picture of The King, will be up for grabs tomorrow at an auction house in Northumberland.
Along with the item comes a letter from a man called Thomas Morgan, who knew Elvis and claims to have been a friend of the singer's hairdresser, Homer Gilleland.
Mr Morgan says that Mr Gilleland accompanied the star on many tours and that the bag of hair clippings he built up was one of his prized possessions.
Jim Railton, from the Northern Auction Centre in Wooler, Northumberland, said he is confident of the item's authenticity.
"We have never sold Elvis' hair before. It came from a deceased estate and we didn't know much about it," he said.
"I processed it quite quickly and did not actually look at the back until someone said there's some stuff behind the picture.
"When we had a look we found some provenance with a certificate saying it was Elvis' hair.
"It's not something you come across every day and it's here to be sold for whatever it makes on the day, there's no reserve.
"It could make £50, it could make £5,000 but it is a rare thing and we are quite confident it is what it says it is."