Ung is a surname.
Ung is a Latin-alphabet spelling of two Cambodian surnames, given below in Geographic Department romanization:
It is the Sino-Korean reading of the Chinese surname Xióng, though that surname is not found modern South Korea. It is also a Scandinavian surname literally meaning "young".
According to the 2010 United States census, roughly 4,519 people in the United States bore the surname Ung, with most (91.79%) being Asian Pacific Americans. As of 2017, 16 people in Denmark and 26 people in Norway bore the surname Ung.