Hardness　and　residual　stress　on　the　surface　serve　as　critical　evaluation　indicators　for　the　quality　of　components　in　industrial　manufacturing.　However,　determining　their　values　becomes　a　substantial　challenge　when　both　these　mechanical　properties　are　variables.　This　study　proposes　a　method　for　decoupling　stress　and　hardness　from　the　time-frequency　domain　of　magnetic　Barkhausen　noise　(MBN),　aiming　to　distinguish　between　the　two　variable　mechanical　properties.　Short-time　Fourier　transform　is　employed　to　obtain　the　amplitude　spectrum　of　MBN,　and　features　in　both　time　and　frequency　domains　are　extracted.　The　relationship　between　the　features　of　MBN　and　mechanical　properties　is　examined.　Our　findings　indicate　that　as　hardness　increases,　the　rate　of　change　of　MBN　features　with　stress　decreases.　In　contrast,　at　higher　stress　levels,　the　rate　of　change　of　MBN　features　with　hardness　increases.　However,　the　frequency　corresponding　to　the　maximum　value　of　the　amplitude　spectrum　fmax　remains　constant　despite　changes　in　stress　but　exhibits　an　increase　with　increasing　hardness.　A　model　based　on　planar　polynomial　functions　related　to　hardness　and　stress　is　developed　to　achieve　decoupling.　The　method　would　serve　as　a　valuable　reference　for　the　decoupling　of　two　or　more　mechanical　properties.