OSG

OSG may refer to:


 * Office of the Solicitor General of the Philippines
 * Office of the Solicitor General of the United States
 * Office of the Surgeon General of the United States
 * Oklahoma State Guard, active during World War II
 * On-site generation of electrical power
 * One Scotland Gazetteer, the definitive national land, property and address dataset for Scotland
 * Open Science Grid, a worldwide collection of technological resources
 * OpenSceneGraph, a 3D graphics programming interface
 * Operational Studies Group, a publisher of wargames related primarily to the Napoleonic Wars
 * Overseas Shipholding Group