Surname テツオ (Tetsuo 
, テツオ , Tetuo 
) , worldwide, is a common family name. The last name テツオ is characteristic of Japan, where it is quite a common surname, Taiwan, where it is a rare surname, and Singapore. Measured by absolute frequency, it is commonest in Eastern Asia, particularly Japan, China, and Taiwan. Much less frequently, テツオ is the forename as well as the last name.