Skeletal remains found along the Shannon Estuary are believed to have been there for more than 10 years.
Gardai are reviewing missing person files after the discovery of the decomposed body in dense undergrowth off the Condell Road in Limerick city.
A Garda spokesman said foul play is not suspected at this stage.
DNA tests will have to be carried out to determine the identity and sex of the victim, who is believed to have died by suicide as a preliminary examination of the scene and body did not reveal a gunshot wound or sign of a violent death.
The remains were discovered around in a nature reserve on the Shannon Estuary.
"The scene has been sealed off for a technical examination," a Garda spokesman added.
"At this early stage foul play is not suspected however investigations are continuing and Gardai are reviewing all missing persons files for the area."