Boron　nitride　nanotubes　were　synthesized　from　boron　oxide　by　high-energy　ball　milling　and　annealing　method.　The　diameter　of　the　nanotubes　is　in　the　range　of　20-200　nm.　The　nanotubes　show　a　bamboo-like　structure　and　cylindrical-like　structure　under　low　magnification.　The　shorter　bamboo　nodes　with　distinct　knots　were　observed　for　the　barnboo-like　nanotubes　with　larger　diameters　and　the　knots　can　also　occasionally　be　observed　in　the　cylindrical-like　BN　nanotubes　with　smaller　diameters　under　high　magnification.　Al　and　Si　were　found　to　be　catalytic　materials　responsible　for　the　formation　of　BN　nanotubes　besides　the　metallic　particles　containing　Fe,　Ni　and　Cr.　(C)　2009　Elsevier　B.V.　All　rights　reserved.