CLH may refer to: Science Chlorophyllase, an enzyme Hydrogen chloride, a chemical compound Companies CLH (company), a Spanish petroleum logistics company comprising Compañía Logística de Hidrocarburos and others CLH Pipeline System (CLH-PS), a UK system run by Compañía Logística de Hidrocarburos Lufthansa CityLine (ICAO code), a German airline Coolah Airport, IATA airport code "CLH" See also CLHS (disambiguation)