Emmanuel Ignatius of Nassau-Siegen (6 January 1688 - 1 August 1735), was a Fieldmarshal of the Spanish and Austrian Army, and Regent of the Principality of Nassau-Siegen in 1727.
Born in Roermond, he was the twenty-second child of John Francis Desideratus, Prince of Nassau-Siegen, but the ninth born from his third and last marriage with the French Isabella Clara du Puget de la Serre.