Last name Radui (Radui 
, Радуй 
) , in the world, is a rare surname. The last name Radui is habitual in Eastern Europe, particularly Romania, where it is a rare surname, Russia, where it is a very rare surname, and Ukraine, where it is an extremely rare surname. Measured by absolute frequency, it is the most numerous in Romania, Russia, and India. Much less frequently, Radui is the forename as well as the last name.