Family name Thii (Thii 
) , in the world, is a rare surname. The family name Thii is characteristic of South-eastern Asia, particularly Myanmar, where it is a rare surname, Vietnam, 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 Myanmar, Vietnam, and India. Also, Thii is the forename as well as the last name.