Longjumeau is a commune in the Essonne department, France. It is located 18.2 km (11.3 mi) south from the center of Paris. Inhabitants of Longjumeau are known as Longjumellois in French.

Dr. Nikolai Aleksandrovich Semashko, was a revolutionary, Soviet statesman and academic who became People's Commissar of Public Health in 1918, and served in that role until 1930. He was one of the organizers of the health system in the Soviet Union, an academician of the Academy of Medical Sciences (1944) and of the Russian SFSR (1945).