This study was carried out to evaluate how broiler chickens respond to corn-soybean meal-based diets enriched with creatine monohydrate (CMH). The effects of CMH at protein levels were observed on performance, nutrients retention, meat water holding capacity (WHC) and blood biochemical parameters in broiler chickens. Three hundred twenty-day-old chicks (Ross 308) were organized in a 2 × 4 factorial arrangement in a completely randomized design, having 4 replicates and 10 birds in each cage (repeat). Diets formulated for two levels of protein (at an amount recommended for Ross 308 and also an amount being 10% higher than the recommendation catalog Ross 308, 2019). Four levels of CMH were used, amounting to 0, 0.1, 0.3 and 0.5% of the diet. In all of the experiment periods the performance results showed that the highest body-weight gain and the lowest feed conversion ratio were observed in high levels of CMH (0.3 and 0.5%) (P<0.05). Feeding the birds with a diet containing protein (high level) led to the highest growth performance (P<0.05). Regarding N loss and nitrogen retention (g bird-1 day-1), the interaction between CMH and protein was significant. Apparent metabolizable energy (AME), N intake (g bird-1 day-1) and N retention (% intake) were affected by protein (P<0.05). The highest WHC was observed in birds that were fed on a diet containing higher amount of protein (P<0.05). Birds fed with 0.3% or 0.5% CMH showed an increase in blood creatinine (P<0.05), as compared to birds fed with 0 or 0.1% CMH. In conclusion, the growth performance of broilers improved by adding 0.3% CMH to the diet, and also birds fed to protein (high level) increased their growth performance. Manuscript profile