To　reduce　crash　rate,　the　access　management(AM)　strategy　was　considered,　and　opposite　vehicle　access　features　of　large　public　buildings　were　analyzed.　A　minimum　opposite　access　spacing　model　was　established　based　on　microscopic　traffic　flow　theory,　and　its　optimization　objective　was　to　eliminate　conflicts　due　to　inadequate　spacing.　The　maximum　spacing　was　deduced　to　keep　access　from　the　functional　area　of　intersections,　and　a　spacing　range　was　formed,　traffic　simulation　and　entropy　weight　method　were　utilized,　and　the　technique　for　order　preference　by　similarity　to　ideal　solution(TOPSIS)　based　on　traffic　conflict　techniques　was　proposed　to　evaluate　the　spacing　schemes　and　search　the　optimal　spacing　from　several　spacing　values.　A　large　public　building　area　was　taken　as　an　example　for　spacing　calculation　and　selection.　Calculation　result　indicates　that　the　range　of　opposite　access　spacing　is　83.98~278.76　m,　its　optimum　spacing　is　120.73　m,　and　the　closeness　degree　of　optimal　solution　is　0.5182.　When　spacing　value　is　in　the　range,　there　is　a　miximum　value　of　closeness　degree.