The　fracture　toughness　of　Ti-48Al-2Mn-2Nb　produced　by　centrifugal　spray　deposition　(CSD)　under　a　low　pressure　vacuum　condition　and　treated　by　hot　isostatic　pressing　(HIP)　at　1　250°C　has　been　investigated　at　ambient　temperature　using　the　three-point　bending　test.　The　results　show　that　the　mean　value　of　fracture　toughness　is　approximately　23.6　MPa　m1/2　and　the　maximum　of　fracture　toughness　reaches　28　MPa　m1/2　for　the　CSD　sample,　while　only　15.3　MPa　m1/2　for　the　HIP　sample.　The　CSD　sample　has　a　finer　lamellar　structure,　but　the　microstructure　of　the　HIP　sample　is　a　duplex　structure　of　lamellar　and　equiaxed　gamma　grains,　for　which　reason　the　much　better　fracture　toughness　the　sample.　The　lamellar　structure　also　has　better　resistance　to　crack　growth　than　equiaked　gamma　grains.