The invention discloses a nail-taking device for bone surgery. A supporting shell is of a cylindrical structure, one end of the inside of the supporting shell is connected with a decelerating motor through bolts, one end of the supporting shell is connected with a connecting rotary shaft through a bearing, an output shaft of the decelerating motor penetrates through one end of the supporting shell, the output shaft of the decelerating motor is connected with one end of the connecting rotary shaft, the inside of the connecting rotary shaft is provided with a slip-connection groove, the extended length of a nail-taking drill can be adjusted by sliding a connecting rod, so that the adjustment of the length of the nail-taking drill is more convenient, through a chuck, a steel nail can be clamped, so that taking of the steel nail is more convenient and the device is prevented from slipping off when the nail is taken, and through a power-driven telescoping rod, one end of each of two Z-shaped supports can be driven to be opened or closed, and the operation is more convenient. The nail-taking device for the bone surgery is simple in structure, can take out the nail at one time, the pain of a patient is relieved, and the operation of taking the steel nail is thus more convenient.