The　separation　of　acetylene　(C2H2)　from　carbon　dioxide　(CO2)　and　methane　(CH4)　is　of　great　significance,　but　remains　challenging,　because　of　their　similar　physicochemical　properties,　and　it　currently　has　received　substantial　research　interest　by　using　adsorptive　separation　based　on　metal-organic　frameworks　(MOFs).　Herein,　a　new　microporous　Cu-MOF,　[Cu(5-OH-IPA2-)-(DPYA)(H2O)]　(BUT-318,　where　5-OH-IPA2-　=　5-hydroxyisoph-thalate　and　DPYA　=　4,4　＇-dipyridylamine)　has　been　synthesized　successfully　under　solvothermal　conditions,　which　exhibits　excellent　separation　performance　for　C2H2/CO2　and　C2H2/CH4　gas　mixtures.　The　presence　of　Cu(II)　open　metal　sites　and　different　Lewis　base　sites　(-OH　and　-NH)　make　the　activated　BUT-318　efficiently　bind　C2H2　and　exhibit　high　adsorption　capacity　under　low　pressure　(24.52　and　9.1　cm3　g-1　under　0.01　bar,　at　273　and　298　K,　respectively).　The　corresponding　IAST　(ideal　adsorbed　solution　theory)　selectivity　was　9.8　and　244.3　at　273　K　and　1　bar　for　an　equimolar　C2H2/CO2　and　C2H2/CH4　mixture.　The　separation　performance　and　reusability　under　dynamic　conditions　were　also　confirmed　by　column　breakthrough　experiments,　making　BUT-318a　a　promising　candidate　for　the　practical　C2H2　separation.