The 15-year-old property with imitation battlements overlooks the Bass Highway near Sassafras and includes a two-storey home, a tea-room, a gallery, turret rooms and a moat.
Another feature of the castle are its gates, which came from the old Ulverstone jail.
Liberty Castle was built by the current owner.
Real estate agent Kim Dougan did not disclose his name.
But she said the building's design had been inspired by the man's childhood love of comics featuring castles and knights.
She said most of the interest in the property had been for a commercial use.
- CAROL MARSHALL