HCY may refer to:
- Homocysteine, an amino acid
- Hôpital Central de Yaoundé, a Cameroonian hospital
- Tsuen Wan Public Ho Chuen Yiu Memorial College, a Hong Kong secondary school
- Helios Airways, a Cypriot airline (1998–2006; ICAO:
HCY
)
HCY may refer to:
HCY
)