Cognomen Buichi (Buichi 
) , worldwide, is a very rare family name. The cognomen Buichi is habitual in Colombia, where it is a very rare surname, China, where it is an extremely rare surname, and India. More prevalently, Buichi is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Buichi | Japan, China, Colombia, India, Brazil |