The invention discloses a special automatic grinding machine capable of loading and unloading automatically for crankshaft processing. The special automatic grinding machine comprises a rack, a clamping part, a grinding part, a power distribution box and a loading-unloading mechanism, wherein the clamping part comprises a first main shaft, a first drive motor, a main shaft tip end, a tail base anda tail base tip end; the grinding part comprises a grinding wheel, a second main shaft and a second drive motor; a crankshaft position measuring head is arranged at one side of the grinding wheel; aPLC controller is arranged in the power distribution box; the loading-unloading mechanism comprises a transmission frame, a loading mechanism and an unloading mechanism, a loading conveyor belt, an unloading conveyor belt and a supporting beam; the loading mechanism comprises a loading clamping jaw, a loading clamping air cylinder and a loading lifting air cylinder; the unloading mechanism comprises an unloading clamping jaw, an unloading clamping air cylinder and an unloading lifting air cylinder; and a crankshaft position measuring head, the first drive motor, the second drive motor, the loading mechanism and the unloading mechanism are connected with the PLC controller. The special automatic grinding machine is high in degree of automation, is high in grinding efficiency, reduces laborpower, reduces cost, is stable and reliable in clamping, and is high in loading and unloading efficiency.