Abstract: A stock separating apparatus which separates stocks that drop successively from a stock feed source through a chute and feeds them one by one to a working machine, for example, a forging press, the apparatus being capable of coping with a change in the size of stocks with ease and within a short time. The stock separating apparatus has an attachment (11) that is provided at the lower end of a chute (3), the attachment being replaceable in accordance with the size of stocks (2). A circularly curved lower chute (6) is provided at the lower end of the chute (3). The attachment (11) is detachably attached to an attachment holder (10) which is horizontally pivotably provided on a support member (12) that is secured to the apparatus body (1) through a bracket (4).