Bomb disposal units were called to the village of Hernhill, near Faversham, this morning after two shells were found.
The explosives were being used as a door stop at a property, where they had been for at least 30 years.
Police were alerted to the discovery at about 11am.
They have been at the scene for several hours.
A police spokesman said that a field has been found for a controlled explosion to be carried out.