The Willits House was built by famed architect Frank Lloyd Wright.
Early Wednesday, police were on the scene. A 51-year old woman was found dead in the home, Highland Park police say.
The woman's husband reported finding her dead and called police, authorities say. She died of an apparent gunshot wound to the head, police say, adding a weapon was recovered at the scene and the public is not believed to be in danger.
An autopsy is pending.