The aim of the present study was to investigate the effects of different copper sources on serum biochemical parameters and the digestibilities of nutrients in growing male sika deer. Twenty 2-year-old growing male sika deer were randomly allotted to four groups (A, B, C, and D) and to study the effects of copper sulfate (group B), copper citrate (group C) and methionine copper (group D) on serum biochemical parameters and nutrient digestibilities. Groups B, C and D were experimental groups and fed diets added 10 mg/kg (copper ion) copper sulfate, copper citrate and methionine copper according to the same energy and nutrient, respectively. The results showed that, 1) the digestibilities of crude protein, calcium in the group of methionine copper were higher than those in other groups (P>0.05); the digestibility of phosphorus in groups C and D was higher significantly than that in other groups (P<0.01); 2) serum copper of male sika deer fed methionine copper was higher than that in other groups (P<0.01) and copper in pelage was significantly higher than that in groups A and B (P<0.05), and fecal copper excretion was lower than that in groups B and C; 3) the effect of different copper sources on the activities of total protein, albumin, alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase in serum were not significantly changed (P>0.05); 4) the effect of methionine copper on the activities of ceruloplasmin and superoxide dismutase were significantly higher than those in group A (P<0.05). It was concluded that methionine copper was the appropriate form in sika deer diet.