HSO

HSO may refer to:

Orchestras

 * Harrisburg Symphony Orchestra, in Harrisburg, Pennsylvania, United States
 * Hartford Symphony Orchestra in Hartford, Connecticut, United States
 * Helena Symphony Orchestra, in Helena, Montana, United States
 * Hereford String Orchestra, in Hereford, England
 * Hillsboro Symphony Orchestra, in Hillsboro, Oregon, United States
 * Hollywood Symphony Orchestra, in Los Angeles, California, United States
 * Houston Symphony, in Houston, Texas, United States
 * Huntsville Symphony Orchestra, in Huntsville, Alabama, United States

Other uses

 * Ford HSO engine
 * Hamburg State Opera
 * Health Sciences Online
 * Healthscope, an Australian hospital operator
 * Herschel Space Observatory
 * Hungarian Space Office