The　spectral　accelerations　(Sa),　which　are　widely　used　as　ground　motion　inputs　in　structural　seismic　designing,　are　significantly　affected　by　local　site　conditions　classified　by　near-surface　geology.　A　novel　approach　of　quantifying　the　scaling　ratios　for　Sa　on　site　class　I,　II,　III,　and　IV　under　the　site　condition　classifications　in　Chinese　seismic　codes,　was　proposed.　In　this　integrated　approach,　the　scaling　ratios　for　Sa　on　each　site　class　were　subordinated　to　three　constituents,　i.e.,　scaling　ratios　for　peak　ground　acceleration　(PGA),　scaling　ratios　for　PGA-normalized　Sa,　and　non-linear　decay　exponents.　The　scaling　ratios　for　peak　ground　acceleration　were　derived　from　recent　studies　and　numerical　simulations　of　1,138　borehole　models　in　China,　the　scaling　ratios　for　PGA-normalized　Sa　were　derived　from　3,584　strong　motion　records　in　NGA　West　two　database,　and　the　non-linear　decay　exponents　were　derived　from　about　140　thousand　borehole　observation　data　recorded　by　KiK-net.　Consequently,　this　approach　was　solidly　based　on　statistics　of　observation　data　in　company　with　numerical　simulations,　which　resulted　in　more　reasonable　and　more　reliable　scaling　ratios　for　Sa　caused　by　the　seismic　site　effect　under　site　condition　classifications　in　China.