IM3 may refer to:
Bristol Pegasus I.M3, a British aero engine Innocenti IM3, a BMC car model Onchan, Isle of Man (Royal Mail postcode IM3) Ia, three-dimensional space group number 206 Indosat Multimedia Mobile (IM3), a telecommunications subsidiary Infamous Mobb (aka "IM3"), an American hip hop group Intermediate 3 (IM3), a competition class under British Rowing Intuitive Machines IM-3, a U.S. commercial lunar lander space mission
See also
Iron Man 3, a 2013 superhero film
IM (disambiguation)
LM3 1M3