Su is the pinyin romanization of the common Chinese surname written in simplified characters and traditionally.
It was listed 42nd among the Song-era list of the Hundred Family Surnames.
It is also the pinyin romanization of the very rare surname .
The Wade form of the name is identical to the pinyin, but it is also sometimes irregularly romanized as Soo.
蘇 and 苏 are also romanized and Sou in Cantonese; Soh and Souw in Southern Min dialects; Soh in Teochew; and Thu in Gan.
This Chinese name is also the source of the Vietnamese surname Tô (Chữ Nôm: 蘇); the Korean surname , which is romanized So; the Japanese surname , which is also romanized ; and the Filipino/Tagalog surname So. Also, the Filipino family name "Solon" is a Hispanized version of So. The Solon clan coming from Cebu are famous for their ancestors who were government officials. The Solons are of Cantonese descent.