Improved　implant-bone　interface　interaction　for　rapid　formation　of　strong　and　long-lasting　bond　is　significantly　important　in　orthopedic　clinics.　Herein,　Ca-doped　TiO2　nanotube　film　(M-CaNTs)　with　enhanced　adhesion　strength　was　fabricated　on　titanium　(Ti)　surface　by　an　anodization–hydrothermal　treatment.　Results　showed　that　TiO2　nanotube　film　(M-NTs)　fabricated　by　modified　anodization　was　amorphous,　exhibiting　100-nm　diameter　and　12-nm　tube　wall　thickness.　After　hydrothermal　treatment,　the　nanotubular　structure　of　M-CaNTs　kept　integrated,　but　was　volume-expanded,　exhibiting　a　decreased　diameter　(∼　60　nm)　and　an　increased　wall　thickness　(∼　30　nm).　The　formation　of　M-CaNTs　proceeded　preferentially　at　the　interior　surfaces　of　the　closely　aligned　nanotubes,　involving　an　in　situ　dissolution–recrystallization　process.　Though　the　adhesion　strength　of　M-CaNTs　was　weakened　by　the　volume-expansion　derived　internal　stress,　it　was　still　higher　than　that　of　the　traditionally　obtained　one.　In　the　in　vitro　investigations,　the　combination　of　nanotubular　structure　and　Ca2+　could　expectedly　enhance　the　attachment,　spreading　and　proliferation　of　MC3T3-E1　cells,　as　well　as　promote　the　expressions　of　bone-specific　genes,　intracellular　proteins　and　ALP　activity,　which　in　turn　accelerated　collagen　secretion　and　ECM　mineralization.　This　work　provides　an　attractive　potential　for　the　surface　modification　of　Ti-based　implants　in　clinical　application.　©　2020　Elsevier　B.V.