HIH may refer to:
- His or Her Imperial Highness, a title still used today for members of Japan's Imperial Family
- HIH Insurance, a former Australian insurance company
- Harstad University College (HiH), a Norwegian state institution of higher education
- High Impact Halo, an Internet fan site for players of the Halo series of video games
- Hih (Korean: 힣), The final set of present Hangul.