MS1

MS1 may refer to:
 * FMA Ae. M.S.1, an air ambulance version of the 1932 Argentine FMA AeC.2 utility aircraft
 * MS1, the first device in tandem mass spectrometry

MS-1 may refer to:
 * Mercury-Scout 1, a 1961 satellite
 * Mississippi's 1st congressional district
 * Mississippi Highway 1
 * Roland MS-1 Digital Sampler
 * T-18 tank
 * A type of Trams of Putilov plant
 * MegaSquirt 'n Spark-Extra (MS1/Extra), a type of MegaSquirt electronic fuel injection controller
 * MS-1 (wrestler), Mexican professional wrestler
 * Metres per second, the SI unit of velocity, written as ms−1
 * A first year medical student
 * MS-1 (spaceplane), a proposed US Spaceplane