Surname สิทธิวิชัย (สิทธิวิชัย 
, Sitiwichai , Sithiwichai ) , all over the world, is a very rare cognomen. The family name สิทธิวิชัย is habitual in South-eastern Asia, particularly Thailand, where it is a rare surname. Very seldom, สิทธิวิชัย is the forename as well as the last name.