In　this　paper,　the　boron-containing　mesoporous　bioactive　glass　(MBG)　nanospheres　have　been　successfully　synthesized　by　modified　sol-gel　method　assisted　by　surfactant,　and　the　effect　of　boron　substitution　on　structure　and　bioactivity　was　evaluated　by　combining　experiments　and　ab　initio　molecular　dynamics　(AIMD)　simulations.　All　of　the　samples　exhibit　regularly　uniform　mesoporous　spherical　microstructure　with　an　average　size　of　about　60 nm,　and　the　boron-containing　MBGs　show　higher　specific　surface　area　with　the　value　up　to　416.20 m2/g.　The　simulated　body　fluid　(SBF)　immersion　test　confirms　that　the　deposited　hydroxyapatite　(HA)　evidently　increases　with　the　increasing　of　boron　content,　indicating　that　the　biological　behavior　has　been　significantly　improved　resulting　from　incorporation　of　boron.　Additionally,　our　results　also　reveal　that　B2O3　substitution　has　positive　impact　on　cell　proliferation　of　human　periodontal　ligament　cells　(hPDLCs)　at　lower　extracted　concentration.　Furthermore,　AIMD　simulation　is　employed　to　understand　the　relationship　between　structural　changes　and　in　vitro　bioactivity　in　terms　of　structural　information,　especially　the　boron　coordination　number.　The　results　illustrate　that　the　boron-containing　MBG　nanospheres　with　excellent　bioactivity　are　great　potential　for　biomedical　applications.　©　2021　The　American　Ceramic　Society