In　2022,　we　proposed　a　VS30　proxy　model　based　on　the　Cokriging　method,　integrating　local　VS30　measurements　with　topographic　slope　data　(SCK　model,　Zhou　et　al.,　2022).　Utilizing　this　model,　a　VS30　map　for　mainland　China　was　developed　based　on　7797　local　boreholes.　However,　the　initial　VS30　map　was　produced　with　a　coarse　grid　resolution　of　360　arcsec　and　did　not　comprehensively　cover　mainland　China　due　to　sparse　distribution　of　boreholes　in　certain　areas.　In　this　study,　we　refined　the　SCK　model　by　explicitly　accounting　for　the　influence　of　surrounding　topographic　slopes,　incorporating　more　distant　VS30　measurements,　and　improving　the　spatial　distribution　of　VS30　measurements　used　in　the　model　calculation.　Tests　based　on　virtual　cases　were　conducted　to　evaluate　the　characteristics　of　the　refined　SCK　model.　In　addition,　142　VS30　measurements　from　strong-motion　stations　in　western　China　were　added　to　enhance　spatial　coverage　and　model　accuracy　in　these　regions.　Employing　the　refined　SCK　model　and　the　expanded　VS30　data　set,　a　new　VS30　map　for　mainland　China　was　generated.　This　updated　map　features　a　higher　grid　resolution　of　30　arcsec　and　covers　the　entirety　of　mainland　China,　showing　reduced　estimation　errors　and　improved　continuity.　Comparisons　with　the　U.S.　Geological　Survey　Global　VS30　Mosaic　indicate　that　the　results　from　the　refined　SCK　model　are　more　reasonable,　as　evidenced　by　local　topography,　VS　profiles,　lithologic　profiles,　and　geology　map,　which　better　capture　the　impact　of　local　geomorphological　differences　and　climatic　conditions　on　VS30　values.　©　Seismological　Society　of　America.