The　NiCrBSi　coatings　were　deposited　onto　St37　steel　substrates　by　microplasma　spraying　(MPS).　The　influence　of　the　spraying　parameters　such　as　substrate　temperature,　plasma　gas　flow　rate,　electric　current　intensity　and　spray　distance　on　the　micro-structure　and　properties　of　coatings　was　investigated　by　means　of　statistical　experimental　design.　The　coatings　were　studied　in　terms　of　their　microstructure　using　optical　microscope.　The　surface　roughness　of　the　coatings　was　measured　by　a　Perthometers　M4P　150.　And　the　oxygen　content　of　the　coatings　was　determined　by　a　LECO　TC316　gas　extract　equipment.　The　results　showed　that　the　spraying　parameters　influenced　significantly　on　the　properties　of　the　coatings.　The　coating　roughness　decreased　with　increasing　current　intensity　and　substrate　temperature.　The　oxygen　content　in　the　coatings　increased　with　increasing　substrate　temperature　and　spray　distance.　Most　of　the　coatings　had　a　hardness　over　600　HV0.2.　The　coatings　exhibited　a　high　bonding　strength　about　more　than　50　MPa　despite　relatively　low　particle　velocities.