The invention relates to a fully-automatic grinder comprising a base, a workbench, a headstock, a tailstock, a grinding wheel mechanism, a feeding and discharging manipulator, an automatic feeding mechanism, an automatic discharging mechanism and a numerical control device. A chuck and a centre are arranged on opposite faces of the headstock and the tailstock respectively and concentrically. The feeding and discharging manipulator comprises a taking pneumatic gripper, a taking cylinder, a putting pneumatic gripper, a putting cylinder, a guide slide fixing frame, a ball screw, a linear guide rail and a guide rail bracket, the taking pneumatic gripper, the taking cylinder, the putting pneumatic gripper and the putting cylinder are all mounted on the guide slide fixing frame, the taking pneumatic gripper and the putting pneumatic gripper are arranged at an included angle forward and backward and arranged parallelly leftward and rightward, and the guide slide fixing frame is in sliding fit with the ball screw and the linear guide rail. The grinder is high in automation degree, the whole process of feeding, discharging, clamping, machining, on-line measurement and the like of workpieces is completed automatically through the numerical control device, one-man multi-machine operation can be realized, production efficiency and production quality are improved, and labor intensity and production cost of workers are lowered.