Article history Received: 26 Jan, 2015 Revised: 3 March, 2015 Accepted: 5 March, 2015 Abstract This investigation was carried out to study different levels of wheat bran on performance of Moghani fattening lambs. Twenty-four male Moghani lambs with mean body weight of 30.42±0.525 kg were used in completely randomized design with four treatments each containing six animals for a total of 84 days feeding trial. Experimental treatments included a diet without wheat bran (control), and treatments consisting of 10, 20 and 30% wheat bran. The results of experiment showed that using different levels of wheat bran had no significant influence on dry matter intake. Use of 20% wheat bran caused a significant improvement in weight gain and feed conversion ratio (FCR) in experimental lambs. The result indicated that wheat bran at the rate of 20% proved to be a good substitution of other valuable grains.