Cotan may refer to:
- Cotangent, abbreviated as cotan, a trigonometric function
People with the surname
- Alin Coțan (born 1982), Romanian footballer
- Antonio Cotán (born 1995), Spanish footballer
- Imron Cotan (born 1954), Indonesian diplomat
- Juan Sánchez Cotán (1560–1627), Spanish painter of still lives
See also
- Kotan (disambiguation)