Family name Koyang (Koyang 
) , around the world, is a rare surname. The cognomen Koyang is characteristic of Cameroon, where it is quite a rare surname, Indonesia, where it is a very rare surname, and Malaysia, where it is an extremely rare surname. Measured by absolute frequency, the name is most common in Cameroon, Indonesia, and India. Likewise, Koyang is the forename as well as the last name.