This study was performed to investigate the effect of excision arthroplasty of femoral head on walking in dogs. Observations of standing, walking and running were made for 6 months after operation. The recovery periods in excision arthroplasty of femoral head were 21～29 and 71～127 days in small and large dogs, respectively. When the biceps femoris muscle was utilized, the recovery period were 21～29 and 43～57 days in small and large dogs, respectively.