Surname Koshan (Koshan 
, Кошан 
) , throughout the world, is quite a rare family name. The family name Koshan is characteristic of Afghanistan, where it is quite a rare surname, Ukraine, where it is a rare surname, and Kyrgyzstan. Not in comparison with a country's population, the name is most common in Afghanistan, Indonesia, and Ukraine. Also, Koshan is the forename as well as the last name.