A corpse was found in a forest between the communities of Lapid and Hashmonaim near the central city of Modiin on Saturday, police said.
Police opened an investigation into the death of the man, in his 50s. It was unclear from the police statement who had found the body.
Officials said the body had apparently been lying in the forest for several weeks.
Criminal investigators conducted a search for evidence in the area, and the body was taken to the Institute of Forensic Medicine in Tel Aviv for further study.