This study was carried out from November 30, 2007 to January 17, 2008 to determine the effects of the combination as well as full replacement of meat and bone meal (MBM) in broiler starter and finisher chickens diets with soybean meal (SBM) on daily feed intake, body weight gain, food conversion rate, water consumption, economic efficiency and carcass characteristics. A total of 306 day old broiler chickens were divided into 18 groups of 17 birds each and subjected to completely randomized design, such that three replicates were allocated to a diet. The diet was isocaloric and isonitrogenous that contained around 3000kcal/kg ME and 22%CP for starter and 3200kcal/kg ME and 20%CP for finisher phase. The diet (experimental) groups were diet 1 (commercial diet) used as comparison purpose; diet 2 (0%SBM + 26%MBM), diet 3 (6.5%SBM + 19.5%MBM), diet 4 (13%SBM + 13%MBM), diet 5 (19.5%SBM + 6.5%MBM), and diet 6 (26%SBM + 0%MBM). The birds were fed and watered ad libitum. At the end of the experiments, 2 broilers (one male and one female) from each replicate were selected and slaughtered to evaluate the development of different cut ups and abdominal fat. The result indicated that feed intake and body weight gain of the birds were significantly (p0.05) for diet 1, diet 5 and diet 6 for the whole period of feeding. The highest feed conversion rate was recorded for diet 2. Higher water to feed ratio were observed in the whole production cycle for diet 1, diet 5 and diet 6. However, rate of survival was not significantly different among treatments (p>0.05). Lack of uniformity in body size and posture of birds was seen as the level of MBM inclusion was beyond 6.5%. Biological and economic efficiencies as measured by the amount of feed and feed cost required per kg live weight gain was significantly higher for the groups fed on diet 5 and diet 6 during the entire study period. The lowest abdominal fat percentage was observed for diet 1 and diet 6, and the highest was recorded for the treatment groups containing 13% - 26%MBM diets, although there was a tendency of increase in abdominal fat with the increase in the level of MBM. Diet 1 comprised significantly (p