Pressure-wave　supercharger　(PWS)　is　one　technical　way　to　boost　the　engine　intake　air　pressure.　PWS　has　several　advantages　such　as　less　emission　(especially　NOx　emission),　rapid　response　when　load　changes,　higher　torque　even　at　low　engine　speed.　In　this　research　a　493　diesel　engine　is　charged　by　a　pressure-wave　supercharger　(PWS).　The　emission　performance　of　the　PWS　diesel　engine　is　mainly　investigated.　Together　with　experimental　test,　the　CFD　simulation　is　completed　basing　on　a　3D　model　of　the　PWS　rotor　channel.　The　CFD　simulation　results　show　that　the　inner　EGR　phenomenon　happens　especially　when　PWS　runs　at　middle　PWS　rotational　speed　with　part　load.　The　test　results　demonstrate　that　the　PWS　diesel　engine　performs　well　with　less　NOx　and　soot　emissions　than　the　turbocharged　diesel　engine.