COO may refer to:
- Country of origin
- Chief operating officer or chief operations officer, high-ranking corporate official
- Cell of origin (telecommunications)
- Certificate of origin, used in international trade
- Carboxylate, type of anion
- Cobalt(II) oxide, chemical with formula of CoO
- Concept of operations, used in Systems Engineering Management Process
- coo, the call of pigeons and doves
- Summer Days with Coo, a 2007 Japanese animated film
People
- Coo Coo Cal (Calvin Bellamy, born 1970), American rapper
- Coo Coo Marlin (1932–2005), racing driver
Places
- Cadjehoun Airport (IATA Code: COO), in Cotonou, Benin
- Calgary Olympic Oval, Canadian ice rink
See also
- Total cost of ownership (TCO)