To provide a non-destructive fruit sorting machine high in the sorting accuracy of fruit.

A sorting machine is equipped with a means for transferring fruit by a conveyor constituted by connecting a large number of links and a means capable of automatically regulating a fixing plate 6 provided with some light sources 5 emitting light. An optical cable 3 is positioned at a place made close to the dispersion preventing cylinder 21b provided to the bottom surface of each of the links 21 constituting the conveyor passing under the light sources 5 so that the lights emitted from the light sources 5 transmit through fruit to arrive at a sensor through the optical cable 3. The optical data recognized by the sensor is processed according to the preliminarily formed standard (calibration curve) of a controller 8 to sort fruit by grade.