Maize shelling is the most important aspect of post-harvest operation of the maize crop. It involves detaching of the maize grain from its cob. The experiments were carried out to develop and construct of a simplified machine for shelling maize grains. The main parts of the developed shelling machine were as follows: feed hopper, shelling chamber, shelling drum, sieved floor, and electrical motor with transmission pulleys and v-belt. The performance of the developed machine was studied under the following parameters:Moisture content of maize grains: 13, 17, 22 %.Drum rotating speeds: 760, 880, and 1080 rpm or (20, 23, 28 m.s-1). Feeding rate: 0.38, 0.40, 0.44 and 0.55 Mg.h-1. The performance of the manufactured machine was evaluated taking into consideration the following indicators: productivity, shelling efficiency, broken ratio, grain losses, energy requirements, operational cost and criterion cost. The experimental results reveal that the highest values of both machine productivity and shelling efficiency were 0.451Mg.h-1 and 90%, respectively. While the lowest values of both specific energy and criterion cost were 3.45kW.h.Mg-1 and 110 L.E.Mg-1, respectively. The optimum operating parameters of the developed shelling machine were found at 880 rpm (23m.s-1) drum speed, 17% grain moisture content and 0.4 Mg.h-1 feed rate.