IHA may refer to:
- Acronyms
- Ice Hockey Australia, Ice Hockey Australia
- Immaculate Heart Academy, Catholic high school in New Jersey
- Imperial Household Agency, the Japanese government agency that oversees Royal affairs.
- Independence Hall Association
- Ingeniørhøjskolen i Aarhus, the Engineering College of Aarhus, Denmark
- Intel Hub Architecture, chipset and bus architecture for Intel Pentium 4, Intel Pentium III-based systems
- International Hydropower Association, a not-for-profit, international organization representing the hydropower sector, with a Central Office located in London, United Kingdom.
- Ihlas News Agency, A Turkish news agency.
- Idiopathic hyperaldosteronism, an endocrinological disease .
- Institute for Healthcare Advancement, a not-for-profit, private operating foundation providing health care and improving health literacy
- Irene Handl Applies, an acronym used on bulletin boards based on her statement that 'I think you've mistaken me for someone who gives a fuck.'