This system is for implementing a method for feeding of a granulated substance, and is provided with: a feeding path through which cut tobacco is fed toward a tobacco band in a cigarette manufacturing machine; a separation device for separating, by winnowing, the cut tobacco into good products and sub-standard products that are heavier than the good products, in the process of feeding the cut tobacco; an adjustment device that is capable of directly and/or indirectly adjusting the velocity of a current of air used for separation through winnowing; a transfer path which receives and transfers the sub-standard products discharged from the separation device; a weighing device which takes a sample of the sub-standard products being transferred on the transfer path and measures the weight of the sampled sub-standard products and outputs the weighing result; and a controller which, on the basis of the weighing result, controls the operation of the adjustment device so as to bring the sampling weight equal to a target value being the management standard.