The bonding characteristics of (0001)α2||(111)γ interface in two-phase TiAl alloy have beeninvestigated with the recursion method. The results of bond order integral and interaction energybetween atoms are presented. The effects of B on atoms bonding both in constituent phase andat the α2/γ interface have been studied. The correlation between the mechanical propertiesof the alloy and the bonding at the interface has been discussed. The results suggest that Bsegregation to the interface benefits the ductility. This is supported by the related experiment. The bonding characteristics of (0001) α2 || (111) γ interface in two-phase TiAl alloy have been investigated with the recursion method. The results of bond order integral and interaction energy between atoms are presented. The effects of B on atoms bonding both in The correlation between the mechanical properties of the alloy and the bonding at the interface has been discussed. The results suggest that Bsegregation to the interface benefits the ductility. This is supported by the related experiment.