MPO may stand for: Astronomy Mercury Planetary Orbiter, one component of the BepiColombo mission to Mercury Minor Planet Circulars Orbit Supplement, an astronomical publication from the Minor Planet Center Minor Planet Observer, an astronomical computer program partially based on the work of Mikko Kaasalainen Science and technology Myeloperoxidase, a peroxidase enzyme most abundantly present in neutrophil granulocytes .mpo file or Multi Picture Object, a 3D computer graphics image file format Medial preoptic area, a portion of the preoptic area of the hypothalamus Multi-fiber Push-On, a type of optical fiber connector Multiset path ordering, a well-ordering in term rewriting (computer science) Matrix Product Operator, a type of tensor network central to the Density Matrix Renormalisation Group numerical technique Organizations Macedonian Patriotic Organization, a United States and Canadian organization supporting Macedonians Metropolitan planning organization, a type of transportation policy-making organization in the United States Malaysian Philharmonic Orchestra, a Malaysian orchestra based in Kuala Lumpur Managerial and Professional Officers, former British trade union Management and Planning Organization of Iran, a now-dissolved organization previously responsible for Iran's budget Other uses Metal Gear Solid: Portable Ops, a 2006 video game released for the PlayStation Portable Military Post Office, a key part of a military mail system Pocono Mountains Municipal Airport, by IATA code Most Productive Overs method in cricket Metropolitan planning organization, a federally mandated and funded transportation policy-making organization in the United States Master of Prosthetics and Orthotics