Cognomen Ryuji (Ryuji 
, リュウジ , ريجي 
) , across the world, is a common surname. The surname Ryuji is characteristic of Japan, where it is quite a common surname, Malaysia, where it is a rare surname, and Singapore. Not in comparison with a country's population, this name is the most popular in Japan, China, and Indonesia. Very seldom, Ryuji is the forename as well as the last name.