It is believed to have been extracted in 1817 during the French general's exile on the British island of Saint Helena, in the South Atlantic Ocean, after his defeat at the Battle of Waterloo two years earlier.
"Historically, we know that Napoleon had had toothache in 1816 and this was put down to a mouth inflammation diagnosed as scurvy," valuer Chris Albury said Tuesday.
"By the time of his death in 1821, he was a physical wreck and his gums were soft and bled easily and his teeth were loose."
The tooth - an upper right canine - is thought to have been extracted by Napoleon's physician Barry O'Meara, who then gave it to General Francis Maceroni, aide-de-camp to the King of Naples.
It stayed in the Maceroni family for generations before it was acquired by its present owner in 1956.
The tooth, estimated to fetch 5,000 to 8,000 pounds, will go under the hammer at the Dominic Winter auction house in Swindon, Wiltshire, in southern England, on November 10.