MS3 may refer to: Mighty Servant 3, a 27,000-ton semi-submersible heavy-lift ship Junior medical student, in the list of medical abbreviations: J Metal Slug 3, a video game MotorStorm: Apocalypse, the third main video game in the series MegaSquirt3, a type of MegaSquirt electronic fuel injection controller
MS-3 may refer to: Mississippi's 3rd congressional district a type of trams of Putilov plant
MS.3 may refer to: Escadrille MS.3, a French air force unit of Escadron de Chasse 01-002 "Cigognes" Morane-Saulnier MS.3, a French parasol wing one or two-seat aeroplane of the First World War
MS 3 may refer to: Mississippi Highway 3