The study was made in order to establishing qualitative indexes of concentrate feeds made by hummer mill MB-7,5 equipped with 3 type of sieves and 2 type of hummers on mill rotor. Granularity tests were made by Sieving Machine AS-300 with 4 sieve-plates. Concentrate feeds were wheat and corn at 2 different humidity levels, from each milling product were tacked 3 samples for Sieving Machine, were made averages to estimate milling module. Results show us the major in luence of grain type (wheat or corn) in granularity determination, humidity of grain modify also our expected results.