In　order　to　eliminate　the　calculation　error　of　the　Hertzian　elastohydrodynamic　contact　stress　due　to　the　asymmetry　of　the　contact　region　of　the　helix　raceway,　a　non-Hertzian　elastohydrodynamic　contact　stress　calculation　method　based　on　the　minimum　excess　principle　was　proposed.　Firstly,　the　normal　contact　stresses　of　the　screw　raceway　and　the　nut　raceway　were　calculated　by　the　Hertzian　contact　theory　and　the　minimum　excess　principle,　respectively.　Subsequently,　the　Hertzian　solution　and　the　non-Hertzian　solution　of　the　elastohydrodynamic　contact　stress　could　be　determined　by　the　Reynolds　equation　under　different　helix　angles　and　screw　speeds.　Finally,　the　friction　torque　test　of　the　double-nut　ball　screws　was　designed　and　implemented　on　a　self-designed　bed　for　validation　of　the　proposed　method.　The　comparison　showed　that　the　experimental　friction　torque　was　the　good　agreement　with　the　simulated　friction　torque,　which　verified　the　effectiveness　and　correctness　of　the　non-Hertzian　elastohydrodynamic　contact　stress　calculation　method.　Under　the　large　helix　angle,　the　calculation　accuracy　of　asperity　contact　stress　for　the　non-Hertzian　solution　was　more　accurate　than　that　of　the　Hertzian　solution　at　the　contact　region　of　ball　screws.　Therefore,　the　non-Hertzian　elastohydrodynamic　contact　stress　considering　the　asymmetry　of　the　raceway　contact　region　could　more　accurately　analyze　the　wear　depth　of　the　high-speed　ball　screws.