The discovery was made at the Burlington Park Forest Preserve in Naperville, Forest Preserve District of DuPage County officials said.
Forest Preserve District of DuPage County officers responded to the area around 2:56 p.m. to conduct a death investigation.
The age, gender and identity of the person who was found dead was not immediately known.
There is no current danger to the public, DuPage County officials said.
No further information was immediately available as authorities continue to investigate.