HPD
- 4-Hydroxyphenylpyruvate dioxygenase
- Croatian Climbing Society
- HPD series of mines
- Hagerstown Police Department (Maryland)
- Haripad railway station
- Haripur Band railway station
- Harpenden railway station
- Helsinki Police Department
- Hematoporphyrin
- Hempstead Village Police Department
- Henderson Police Department
- Hialeah Police Department
- Hillsboro Police Department (Oregon)
- Histrionic personality disorder
- Hollywood Police Department (Florida)
- Holyoke Police Department
- Honda Performance Development
- Honolulu Police Department
- Hoonah Police Department
- Houston Police Department
- New York City Department of Housing Preservation and Development