A spectacle lens design system is provided with: a first imaging device disposed at a first distance away from a subject and that captures images of the subject; a second imaging device that captures images of an object to be viewed and that is disposed at a second distance away from the subject that is farther separated from the subject than the first distance; a determination means that determines the eye position of the subject on the basis of images captured by the first imaging device; an object-to-be-viewed confirmation means that provisionally calculates the position of the object to be viewed on the basis of images captured by the second imaging device and that confirms the provisionally calculated position of the object to be viewed on the basis of the relative position/orientation relationship between the first imaging device and the second imaging device; a sightline-information calculation means that calculates sightline information for the subject on the basis of the determined eye position and the confirmed position of the object to be viewed as the subject views the object to be viewed; and a shape design means that designs the shape of a spectacle lens on the basis of designated prescription information and the calculated sightline information. Furthermore, the system is provided with an artificial movement means that detects the position and posture of the head of the subject at designated time intervals on the basis of images captured by the first imaging device and that artificially moves the confirmed position of the object to be viewed only as much as the difference in the position and posture of the head of the subject before and after the detections such that the before-and-after-detection position and posture of the head are artificially maintained. The sightline-information calculation means calculates sightline information on the basis of the determined eye position and the artificially moved position of the object to be viewed.