KH may refer to:
- KH Engineering, an international engineering company and EPC contractor. Head office in Schiedam, The Netherlands.
- Cambodia (Kampuchea, Kampocha, Kamboja) ISO 3166-2 alpha code
- .kh, the Internet country code top-level domain for Cambodia
- Kingdom Hearts — a Disney and Square Enix video game series
- Kingdom Hearts (video game) — the first game in the series
- Khornerstone — a computer benchmark
- Kh (digraph) — in English transliteration from numerous foreign languages, usually represents, but sometimes .
- KH (hardness) — a measure of the hardness of water (calcium carbonate concentration)
- Kelvin–Helmholtz instability — a phenomenon of fluid mechanics
- Kh factor - a constant used in electrical metering which corresponds to the number of watt-hours used per revolution of the meter disc
- Potassium hydride, chemical formula KH
- Key Hole (KH) series of imaging satellites used by various United States agencies
- A knight of the Royal Guelphic Order (KH)
- KH - Henry's Law constant