With　the　optimization　goal　of　improving　the　transmission　efficiency　of　the　magnetically　coupled　resonant　wireless　power　transmission　(MCR-WPT)　system,　the　influencing　factors　and　suppression　methods　of　frequency　splitting　phenomenon　(FSP)　are　analyzed　from　the　perspective　of　input　impedance　based　on　the　mutual　inductance　model.　Then　we　propose　the　Monte　Carlo-Interior　Point　method　(MC-IPM)　for　nonlinear　modeling　to　determine　the　optimal　system　parameters　while　ensuring　that　the　system　does　not　suffer　from　FSP.　Finally,　the　simulation　results　show　that　the　proposed　method　can　obtain　the　optimal　parameters　faster　and　achieve　higher　transmission　efficiency.　The　optimized　system　can　meet　the　practical　requirements　and　provides　a　reference　value　for　improving　the　transmission　performance　of　MCR-WPT.　©　2023　by　the　authors.