We report the results of an experimental study to investigate the recovery of the mechanical strength of the tendon to bone implantation. The calcaneus tendon of the rabbit was chosened for study in this experiment, and Material Testing System was used for evaluation of recovery of the mechanical strength of tendon to bone implantation. In our experimental study, 8 weeks after tendon was implanted to bone, the mechanical strength had nearly reached to 90% of the controls. After 8 weeks, the longer the leg was immobilized, the weaker the tendon became. The position of fixation of the leg, extension or flexion, did not make much difference in their recovery of strength.