Olmen Zoo is a zoo in the Belgian village Olmen which is part of the town of Balen.
The zoo was opened in 1976 by Louis Roothooft, a former captain. He used to live near Antwerp where he had a private collection of foreign animals. He bought some land in Olmen and moved his animals to the new location. The Olmen Zoo was founded. As Roothooft loved the circus a big circus tent was soon placed. Each day the animal carers did performance acts with the animals. Roothooft died mid 1990s and the park was sold to the family Verheyen in 1995.
The new owners also had a private collection of animals which were now transported to Olmen. The park was in a bad condition due to mismanagement of Roothooft, cages were not adapted to the animal needs and the number of customers was too low to make sufficient profits.