MRO
- Hokuriku Broadcasting Company
- Hood Aerodrome
- London Metropolitan Archives
- London Metropolitan Archives
- MRO-A
- Macedonian Revolutionary Organization
- Magdalena Ridge Observatory
- Main refinancing operations
- Maintenance, repair and operations
- Marathon Oil Corporation
- Marlborough (disambiguation)
- Mars Reconnaissance Orbiter
- Mary Rambaran-Olm
- Mauritanian ouguiya
- Maximo (software)
- Melrose Industries
- Metsähovi Radio Observatory
- Midwest Reliability Organization
- Mini Racing Online
- Mitochondrion-related organelle
- Morradoo railway station
- Mountains and Rivers Order
- Mr. O
- Mro (Unicode block)
- Mro language
- Mru (disambiguation)
- Mru language
- Murchison Radio-astronomy Observatory
- Oriental Revolutionary Movement