Cereals starch is the major source of energy in the diet of livestock. In recent years, feed processing methods have been used to increase the efficiency of consumption in better digestion of starch in the rumen of livestock. Since the processing operation is energy intensive, many innovations have been made in the field of processing methods in order to increase product quality and reduce energy consumption. One of these innovations is the use of rotating rollers to flake cereals, which has attracted the attention of many researchers in the last half-century. Gelatinized starch is more digestible. Humidification and steaming of the starch granules in cereals cause them to swell and gelatinize. In this research, a tank with capacity of about 10 kg with a stirrer was designed and built. The stirrer receives its driving force through the chain power transmission unit from the driven roller shaft. The stirrer consists of a shaft with a diameter of 20 mm as well as an adjustable sliding outlet with the output flow of 700 g min -1 . To prevent the stickiness of wet sorghum seeds five fingers with the length of 90 mm was installed on the stirrer shaft. The sorghum sample was dropped from the tank outlet onto four metallic guided plates installed in the space between the outlet and the rollers, and then was guided evenly to a distance of 200 mm between the rollers. The distance between the rollers was adjusted by two screws mounted on the chassis. For varying the rotational speed of the rollers, a three-phase 4000 W motor with a 3700 W inverter to control the input frequency of the motor were used. Sorghum grain flaking experiments were performed with four moisture contents of 8.9%, 18%, 21%, and 24%, three rotational speeds of 36, 50, and 64 rpm, and two distance between the rollers of 0.5 and 1 mm in three replications. The moisture content of the samples was measured after flaking in order to study the effect of the initial moisture content, rotational speed, and rollers distance. After processing, the weight percentage of the particles was determined with series sieves of a vibrating sieving device with holes having sizes of 6.35, 5.08, 4.23, 3.17, 1.58, and 0.84 mm. The processing index was calculated using the ratio of the volume mass of the grain processed by the rotating rollers to the volume mass of the grain before processing. The experimental data were analyzed based on a factorial design of split plots. The results showed that the highest weight percentage of the complete sorghum flakes was belonged to the initial moisture content of 21%, the rotational speed of 64 rpm, and the rollers distance of 1 mm. Also, the highest processing index was related to the initial moisture content of 21%, the rotational speed of 50 rpm, and the rollers distance of 0.5 mm. Keywords : Sorghum, Flaking, Steam roller, Processing index, Rotating roller.