A weight sorter capable of carrying out calibration automatically, and a weight sorter of a comparatively simple construction capable of reliably transferring an object to be sorted and weighing the object. A first weighing unit (2) weighs the objects one by one, a sampling means (5) performs sampling of the objects, the second weighing unit (6) weighs the samples, and a calibrating unit compares the weight of each sample measured by the first weighing unit (2) with that measured by the second weighing unit (6) to perform calibration by judging whether or not the difference between the weights is in a predetermined error range. An intermittently rotating transfer roller (32) having a plurality of transfer pockets (321) in its outer circumferential surface is provided as a transfer means (3) for transferring one by one the objects to the weighing unit (2).
