The　effective　permselective　pervaporation　of　alcohol　is　one　of　key　technology　for　bio-alcohol　industrial　production.　In　this　work,　a　new　polydimethylsiloxane-block-polyphenylene　oxide　(PDMS-b-PPO)　copolymer　was　first　synthesized　by　a　bridge　reagent　technique.　Based　on　the　copolymer　structure　confirmation,　the　asymmetric　PDMS-b-PPO　membrane　was　subsequently　prepared　by　phase-inversion　method　in　order　to　improve　the　anti-swelling　capacity　of　PDMS.　SEM　observation　indicated　that　the　morphology　of　as-prepared　membrane　exhibited　a　＇non-perforated＇　structure,　resulting　from　the　phase-inversion　and　micro-phase　separation　of　the　PDMS-b-PPO　copolymer　in　the　membrane　forming　process.　Furthermore,　the　structure　changes　of　the　membranes　with　different　ratio　of　PDMS　to　PPO　were　investigated.　This　non-perforated　structure　in　the　membrane　favored　to　reduce　the　diffusion　resistance,　together　with　the　affinity　of　PDMS　segment　to　alcohol　during　pervaporation　process.　Thus,　the　prepared　PDMS-b-PPO　membrane　showed　dramatically　increased　flux,　in　pervaporation　separation　of　alcohol/water　mixture.　The　flux　of　the　PDMS-b-PPO　membrane　(PDMS　content　of　42.4%)　can　reach　3816.8　g/(m(2).h),　along　with　8.53　of　separation　factor　in　pervaporation　of　5　wt%　alcohol/water　mixture　(60　degrees　C).　This　work　may　provide　a　new　strategy　to　design　and　fabricate　new　copolymer　membranes　for　improving　alcohol　permselective　pervaporation.