Experiments were carried out to evaluate the performance of a farm residues chopping machine so as to use final product for producing animal feed. The performance of the chopping machine was studied under three different types of farm residues [rice straw, sweet potatoes vines and peanut vines], four different cutting drum speeds and four different feed rates. The performance of the chopping machine was evaluated taking into consideration machine productivity, required power, specific energy, operational cost and criterion cost. The experimental results reveal that the optimum values of machine productivity were 258.26, 339.16 and 282.38 kg/hr; the optimum values of the required power were 3.17, 2.85 and 2.90 kW; the optimum values of the specific energy were 12.27, 8.40 and 10.27 kW.hr/Mg; the optimum values of operational cost were 91.88, 69.97 and 84.04 LE/Mg and the optimum values of criterion cost were 102.38, 81.49 and 93.32 LE/Mg for rice straw, sweet potatoes vines and peanut vines, respectively. The mentioned optimum values were achieved under the following conditions: cutting drum speed of about 1520 rpm corresponding to (33.41m/sec.) for different farm residues with adjusting feed rates at 283.15, 400 and 320 kg/hr., for rice straw, sweet potatoes vines and peanut vines, respectively.