Cartilage　defect　repair　by　hydrogel-based　tissue　engineering　is　becoming　one　of　the　most　potential　treatment　strategies.　In　this　work,　a　thermogel　of　triblock　copolymer　poly(lactide-co-glycolide)-block-poly(ethylene　glycol)block-poly(lactide-co-glycolide)　(PLGA　PEG　PLGA)　was　prepared　as　scaffold　of　bone　marrow　mesenchymal　stem　cells　(BMMSCs)　for　repair　of　full-thickness　articular　cartilage　defect.　At　first,　the　copolymer　solution　showed　a　reversible　sol　gel　transition　at　physiological　temperature　range,　and　the　mechanical　properties　of　such　thermogel　were　high　enough　to　support　the　repair　of　cartilage.　Additionally,　excellent　biodegradability　and　biocompatibility　of　the　thermogel　were　demonstrated.　By　implanting　the　BMMSC-encapsulated　thermogel　into　the　full-thickness　articular　cartilage　defect　(5.0　mm　in　diameter　and　4.0　mm　in　depth)　in　the　rabbit,　it　was　found　that　the　regenerated　cartilage　integrated　well　with　the　surrounding　normal　cartilage　and　subchondral　bone　at　12　weeks　post-surgery.　The　upregulated　expression　of　glycosaminoglycan　and　type　II　collagen　in　the　repaired　cartilage,　and　the　comparable　biomechanical　properties　with　normal　cartilage　suggested　that　the　cell-encapsulated　PLGA　PEG　PLGA　thermogel　had　great　potential　in　serving　as　the　promising　scaffold　for　cartilage　regeneration.