HO-1

HO-1 may refer to:


 * Sud-Ouest YHO-1, the Sud-Ouest Djinn
 * Heme oxygenase 1, an enzyme that is induced in response to stress
 * Hiller HO-1 Pawnee, redesignated as Hiller VZ-1 Pawnee
 * Ho-1 cannon, a Japanese autocannon of World War II
 * Cherry Grove, HO-1, a site on the National Register of Historic Places in Maryland
 * (8037) 1993 HO1, a near-Earth asteroid