Performance of the prototype hammer mill machine, in terms of crushing capacity (kg/h), crushing efficiency (%), mean particle size (mm), fuel consumption (ml/kg) or energy consumption (wh/kg) was evaluated. Tests were carried out at engine speeds of 540, 720, 900 rpm, screen hole diameter of 2, 4, 6 mm and feed rates of 3.50, 7.00, 10.50 kg/min.