Cognomen Кусан (Kusan 
, Кусан 
, Kousan 
) , worldwide, is quite a rare last name. The surname Кусан is habitual in Japan, where it is a rare surname, Malaysia, and Croatia. Not in comparison with a country's population, it is commonest in Japan, India, and Malaysia. More prevalently, Кусан is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Kusan | Malaysia, India, Japan, Indonesia, Turkey |
| Кусан | Russia, Ukraine, Kazakhstan, Kyrgyzstan |
| Kousan | United States, India |