The experiment was conducted to study the requirements of energy and protein of 0-4 wk Huaibei Ma chicks by investigating the effects of dietary ME (metabolizable energy) and CP (crude protein) on growing performance,body composition,and deposition of energy and protein.Eight hundred and ten Huaibei Ma chicks of 1-d-old were assigned to 9 dietary treatments following a 4-week experimental period.Nine dietary treatments were formulated to contain 10.90,11.40 and 11.90 MJ/kg ME and 19.0%,17.7%,and 16.4% CP respectively.Dietary ME,CP and interaction between ME and CP had significant effects on growing performance,body composition,and deposition of energy and protein of 0-4 wk Huaibei Ma chicks (P<0.05).Chicks fed with low-ME-high-CP diet had lower feed intake than that in other dietary treatments (P<0.01).Average daily gain was significantly higher in chicks fed with high-ME-high-CP,high-ME-normal-CP and low-ME-low-CP diets,and was significantly lower in normal-ME and low-ME-high-CP diets (P<0.01).Chicks had higher feed efficient in high-ME-high-CP treatment and had higher body fat percent in high-ME-low-CP treatment than that in other treatments (P<0.01).Highest energy deposition efficiency was found in high-ME-low-CP and low-ME-low-CP treatments,and lowest in medium-ME-medium-CP treatment (P<0.01).Highest nitrogen deposition efficiency was found in high-ME-medium-CP treatment in 0-2 weeks and low-ME-low-CP diet in 0-4 weeks,and lowest in medium-ME-medium-CP dietary treatment (P<0.01).There was no increase in nitrogen deposition efficiency as ME increased in low CP diet and as CP increased in low ME diet. In conclusion,ME and CP requirements in diet in 0-4 weeks Huaibei Ma chicks should be 11.90 MJ/kg and 17.7% or 10.90 MJ/kg and 16.4%.