A defect detecting apparatus detects a defect that is present on the outer circumferential surface of work having the outer circumferential surface thereof formed as a bent surface. The defect detecting apparatus is provided with: a jig which supports the work, and holds the work in a state wherein the work is rotated by a predetermined angle; an image pickup device, which picks up an image of the outer circumferential surface of the work held by the jig, the work being in the state wherein the work is rotated by the predetermined angle; and a controller, which processes an image obtained by means of the image pickup device, and determines a defect. The controller stores information relating to the shape of the outer circumferential surface of the work, and information relating to the positional relationship, at each rotation angle, between the image pickup device and a work area having the image thereof picked up by the image pickup device, and the control apparatus uses the information at the time of determining the defect.