Johan van Oldenbarnevelt (Dutch pronunciation: [ˈjoːɦɑɱ vɑn ɔldə(m)ˈbɑrnəvɛlt]), Heer van Berkel en Rodenrijs (1600), Gunterstein (1611) and Bakkum (1613) (14 September 1547 – 13 May 1619) was a Dutch statesman who played an important role in the Dutch struggle for independence from Spain.

Van Oldenbarnevelt was born in Amersfoort. He studied law at Leuven, Bourges, Heidelberg and Padua, and traveled in France and Italy before settling in The Hague. He supported William the Silent in his revolt against Spain, and fought in William's army. In his later years he was a supporter of the Arminians, in the religious-political controversy which split the young Dutch Republic. He is the founder of the Dutch East Indies Company.