The objective of the present research was to compare the availability of zinc in the form of organic zinc, zinc amino acid chelate, with in the form of sulfate in growing pigs. Twenty-five pigs of 25 d-old were divided into 5 groups. Five pigs of each group were fed a basal diet which was a commercial ration without supplying zinc or diets added 25, 50 or 100mg/kg dry matter zinc in the form of amino acid chelate, or 100mg/kg dry matter zinc in the form of sulfate for 30d. The basal diet contained 47mg/kg of zinc and did not satisfy its requirement for the pigs. The diets contained twice more calcium and 15 times more copper than the requirements for the pigs. Femoral and serum zinc concentrations were increased with supplying zinc amino acid chelate and were significantly higher in pigs given the organic zinc than in those given the inorganic zinc at the level of 100mg/kg diet. Zinc solubility in ileal digesta was gradually increased with supplying the organic zinc. Additionally, zinc solubility tended to be higher in the pigs given organic zinc than in those given the same amount of inorganic zinc. These results suggested that the availability of organic zinc was higher than inorganic zinc in the pigs fed a high calcium and copper diet, which, at least partly, resulted from the higher solubility of organic zinc in the ileum.