To provide a grinder which is improved in grinding accuracy and grinding efficiency a crank work.

According to the structure of the grinder, tables 12A, 12B are arranged on the upper surface of a bed 11 in a manner capable of approaching each other, headstocks 16A, 16B are mounted on the tables 12A, 12B, respectively, and first and second bearing mechanisms 17A, 17B are mounted on the tables 12A, 12B, respectively. Then, the tip of a journal 22a of the crank work 22 is borne by the first bearing mechanism 17A, and a pin 22c of the crank work 22 is borne by the second bearing mechanism 17B. Further, the crank work 22 is rotated about the journal 22a, and the peripheral surface of the journal 22a and the peripheral surface of the pin 22c are simultaneously ground.