The remains were discovered in dunes.
Skeletal remains which could date as far back as Famine times have been found on the Donegal coastline.
The remains were discovered in dunes at the shore front at Mountcharles on Friday.
The discovery was made by a visitor who was walking in the area and noticed the remains protruding from the dunes.
A spokesman at Donegal town Garda station confirmed gardaí attended the scene. Gardaí called in an expert to examine the remains.
The remains have been taken to the National Museum in Dublin where they will undergo further testing to establish their age.