Enzymatic hydrolysis of cuttlefish viscera by Protamex, Pepsin, Delvolase and Multifect Neutral was investigated in a batch reactor during 6 hours with an hourly sampling. The influence of the enzyme used and the hydrolysis conditions (operating pH, temperature) was studied with regards to the extent of proteolytic degradation and to molecular weight distribution of the peptides. After 360 min of hydrolysis, cuttlefish viscera treated with Pepsin yielded significantly (p < 0.05) higher protein recoveries compared to the substrate autolysed or treated with other external proteases. However, the amino acid composition showed that this was Protamex hydrolysis which gave the highest percentage of essential amino acids. At least, according to the FPLC patterns, the cuttlefish protein hydrolysates (CPH) were rich in low-molecular-weight peptides, especially with Protamex and Pepsin.