LMO may refer to:
Science and technology Lanthanum manganite (LaMnO3), an inorganic compound Lithium ion manganese oxide battery (LiMn2O4, etc., or LMO), a cathode material for lithium-ion batteries Lithium molybdate (Li2MoO4), an inorganic compound Living modified organism or genetically modified organism Lunar magma ocean, layer of molten rock theorized to have been present on the surface of the Moon
Other uses Lombard language (ISO 639:1 code), of northern Italy and southern Switzerland RAF Lossiemouth (IATA airport code), Scotland LMO (album), by Rage and Lingua Mortis Orchestra Lego Minifigures Online, a defunct massively multiplayer video game