Su, also spelled Soo, is a rare Korean surname, a single-syllable Korean given name, and an element in many two-syllable Korean given names.^[1] As given name meaning differs based on the hanja used to write it. There are 91 hanja with the reading "su"^[2] on the South Korean government's official list of hanja which may be registered for use in given names.

As a family name, Su(Soo) may be written with two different hanja, each indicating different lineages. The 2000 South Korean Census found a total of 199 people and 54 households with these family names.^[3]

The more common name means 'water' (水; 물 수). The surviving bon-gwan (origin of a clan lineage, not necessarily the actual residence of the clan members) as of 2000 included Gangneung, Gangwon Province (46 people and 12 households); Gangnam, Seoul (41 people and 9 households); Gimhae, South Gyeongsang Province (17 people and four households); Gosan (today Wanju County), North Jeolla Province (11 people and three households); and nine people with other or unknown bon-gwan.^[3][4] According to the Joseon Ssijok Tongbo (조선씨족통보; 朝鮮氏族統譜), the name originated in Wuxing (today Wuxing District, Huzhou), Zhejiang, China.^[4][5]

The less common name means 'shore' or 'bank' (洙; 물가 수). For the 75 people with this family name, the surviving bon-gwan as of 2000 included Dalseong County, Daegu (46 people and 15 households); Miryang, South Gyeongsang Province (24 people and eight households); and five people with other or unknown bon-gwan.^[3][6]

As given name meaning differs based on the hanja used to write it. There are 91 hanja with the reading "su"^[7] on the South Korean government's official list of hanja which may be registered for use in given names.

People with the given name Soo include:

• Go Soo (born 1978), South Korean actor

Korean names which begin with this element include:

Korean names which end with this element include:

• List of Korean family names
• List of Korean given names