Police said they were called to the A28 Station Road, Northiam, just after 1pm.
A police spokesman said they were responding to reports of a possible explosive device which was found in a garden.
As a result, properties on either side of the garden have been evacuated, police said.
The Explosive Ordnance Disposal (EOD) was on its way to the scene, police added.
A police spokesman could not confirm what sort of devise had been discovered.
There are no reports of any road closures.