To investigate the nutritional properties of European eel muscle protein， the amino acids composition and in vitro digestion characteristics of muscle and its isolated water-soluble protein(WP) and salt-soluble protein (SP) were analyzed. The essential amino acids of muscle， WP and SP accounted for 37.81%， 36.53% and 42.71%， respectively. Valine was the first limiting amino acid of muscle protein and SP， while that of WP was methionine + cysteine. The essential amino acid index， biological value and protein efficiency ratio of SP were 98.72， 95.91 and 3.90， respectively， which were significantly higher than those of WP. The SDS-PAGE result indicated that WP was more digestible by pepsin than SP. After being heated with eel muscle oil， the free amino acids in the in vitro digested products of WP and SP increased significantly， while the digestion of casein were inhibited. Based on the present result， it is concluded that the nutritional value of SP in the European eel muscle is higher than that of WP， and heating treatment can promote the digestion of WP and SP.