Aiming　at　the　problem　that　the　machining　coordinate　calculation　of　non-circular　surface　parts　tangential　point　tracing　grinding　was　complicated,　a　method　to　describe　the　tool　path　by　adopting　the　angle　between　the　curvature　circle　tangent　and　pole　connection　at　the　grinding　point　was　proposed,　and　a　new　non-circular　curve　X-C　linkage　machining　model　was　established.　The　non-circular　X-C　machining　coordinate　computational　formula　with　machining　allowance　was　designed,　and　the　model　error　was　analyzed　from　allowance,　wheel　radius　and　model　calculation　error.　The　oval　piston,　square　tools　cutter　and　cam　processing　were　taken　as　example　respectively　to　verify　the　processing　simulation　and　model　error　by　using　wheel　reversal　experiment.　The　processing　simulation　and　processing　experiment　results　showed　the　correctness　of　X-C　processing　model.