Siah may refer to:
- She (surname), a Chinese family name
- Siah (group), an Israeli left-wing group
- Siah, Iran, a village in Ardabil Province, Iran
- Siah Jamegan F.C., an Iranian football club
People
- Siah Albison, British runner
- Siah Khan, Iranian record holder
- Siah and Yeshua DapoED, American hip hop duo