Jean-Jacques Madeleine Willmar (March 6, 1792 – November 26, 1866) was a Luxembourgian politician and jurist. An Orangist, he was the second Prime Minister of Luxembourg, serving for five years, from December 6, 1848 until September 23, 1853.Born in 1792 in the city of Luxembourg, he was the son of Jean-Georges Willmar, who was governor of the Grand Duchy of Luxembourg from 1817 to 1830.In 1814 he received his Licence in Law in Paris, and became a lawyer at the bar of Luxembourg city.