The aim of the present study was to investigate the effect of reduced dietary protein levels on some behavioral patterns, and productive traits of the Muscovy duck. Ninety ducks of six weeks of age were divided equally into three treatments of 30 birds. Treatments were designed according to the protein level in the ration into 22%, 18% and 14% crude protein (CP). All groups received a starter diet of 22% protein from one day old until 6 weeks old. Two treatment groups received reduced protein levels, 18 % and 14%, while the third (control) group continued with 22% protein till the end of the experiment at 12 weeks old (control). Behaviors (ingestive, standing, walking, resting, and feather pecking) were measured during the whole study. In addition, body weight, average daily gain (ADG), feed intake, and relative growth rate (RGR) were measured throughout the experiment on a weekly basis. Birds fed on 14 % crude protein recorded the highest significant values for feeding, standing, walking, vent pecking and litter eating times in comparison to other treatments. Our results showed that severely decreasing dietary CP had significant (P < 0.05) negative effects on BW, ADG and feed intake of Muscovy ducks during finishing period. However, birds fed on 18 % crude protein had better feed conversion ratios during the last 3 weeks of experiment and recorded the highest significant values for ADG. Feeding Muscovy ducks on 18 % CP during the finishing period (6-12 weeks) could be utilized advantageously to improve body weight, ADG and RGR with low feed intake and cost.