HYL or hyl may refer to:
- Hyl (unit), a unit of mass also known as the metric slug
- Hayle railway station, in England
- Helsingin yhteislyseo, a school in Kontula, Helsinki, Finland
- Hollis Seaplane Base, in Alaska, United States
- Hydroxylysine, an amino acid
- Nils Hylander (1904–1970), Swedish botanist and mycologist; author abbreviation: Hyl.