An object identification system comprising: acquiring means configured to acquire a captured image of each of a plurality of objects respectively having peculiar patterns on surfaces thereof, predetermined images being formed on the surfaces; classifying means configured to classify, for each of the plurality of objects, the object into any one of a plurality of classifications according to a deviation of a position where the predetermined image is formed with respect to a reference position on the object, or according to a pattern of noise included in the predetermined image formed on the object, in the captured image acquired concerning the object; registering means configured to register in association with one another, for each of the plurality of objects, identification information of the object, a surface pattern image indicating a pattern on the surface of the object, and the classification of the object classified by the classifying means; target object acquiring means configured to acquire a captured image of a target object obtained by capturing an image of the target object; classification acquiring means configured to acquire classification candidates for the target object, on the basis of a result obtained by the classifying means which is further configured to classify the target object into any one of the plurality of classifications on the basis of the target object captured image obtained by the target object acquiring means; pattern-image acquiring means configured to acquire the surface pattern images registered by the registering means in association with the classification candidates acquired by the classification acquiring means; and specifying means configured to specify, as identification information of the target object, identification information associated with a surface pattern image, among the surface pattern images acquired by the pattern-image acquiring means, that matches a target surface pattern image of the target object acquired from the target object captured image. acquiring means configured to acquire a captured image of each of a plurality of objects respectively having peculiar patterns on surfaces thereof, predetermined images being formed on the surfaces; classifying means configured to classify, for each of the plurality of objects, the object into any one of a plurality of classifications according to a deviation of a position where the predetermined image is formed with respect to a reference position on the object, or according to a pattern of noise included in the predetermined image formed on the object, in the captured image acquired concerning the object; registering means configured to register in association with one another, for each of the plurality of objects, identification information of the object, a surface pattern image indicating a pattern on the surface of the object, and the classification of the object classified by the classifying means; target object acquiring means configured to acquire a captured image of a target object obtained by capturing an image of the target object; classification acquiring means configured to acquire classification candidates for the target object, on the basis of a result obtained by the classifying means which is further configured to classify the target object into any one of the plurality of classifications on the basis of the target object captured image obtained by the target object acquiring means; pattern-image acquiring means configured to acquire the surface pattern images registered by the registering means in association with the classification candidates acquired by the classification acquiring means; and specifying means configured to specify, as identification information of the target object, identification information associated with a surface pattern image, among the surface pattern images acquired by the pattern-image acquiring means, that matches a target surface pattern image of the target object acquired from the target object captured image.