The　influence　of　surface　roughness　such　as　short　fibers　on　sound　propagation　in　cylindrical　micro-tubes　is　investigated,　both　theoretically　and　numerically.　Based　on　the　calculated　velocity　and　temperature　fields,　a　theoretical　model　is　developed　to　evaluate　the　sound　propagation　performance　of　composite　micro-tubes　containing　periodical　fibrous　surface　roughness　elements.　Finite　element　models　are　developed　to　validate　the　theoretical　model,　with　good　agreements　achieved.　The　sound　propagation　performance　of　micro-tubes　with　surface　roughness　is　compared　with　that　of　micro-tubes　without　surface　roughness,　with　the　influence　of　roughness　geometry　on　sound　propagation　systematically　investigated.　Surface　roughness　can　dramatically　increase　the　sound　energy　consumed　by　viscous　effect　and　decrease　the　sound　energy　consumed　by　thermal　effect,　resulting　enlarged　sound　absorption.　(C)　2016　Elsevier　Ltd.　All　rights　reserved.