Enzymic mixtures were prepared from digestive organs of the three species of sea Snails. All the three mixtures can break down the cell-walls of seaweeds.The present paper reports only three of the enzymic components in these mixtures, two cellulates (Cx,C1) and one pectinase.The level of activity of the cellulose Cx is in the order: Lunclla cornata coreensis > Monodonta labio > Purpura clavigera,and of the cellulate C1 is in the order: L.. cornata coreensis >> M. labio= P clavigera. These two cellulases play an important role in decomposing cell walls of seaweeds.The level of activity of the pectinase is in the order of M,. Iahio > L. cornata coreensis > P. clavigera. Enzymic mixtures were prepared from digestive organs of the three species of sea Snails. All the three mixtures can break down the cell-walls of seaweeds. The present paper reports only three of the enzymic components in these mixtures, two cellulates (Cx, C1) and one pectinase. The level of activity of the cellulose Cx is in the order: Lunclla cornata coreensis> Monodonta labio> Purpura clavigera, and of the cellulate C1 is in the order: L .. cornata coreensis >> M. labio = P clavigera . These two cellulases play an important role in decomposing cell walls of seaweeds. The level of activity of the pectinase is in the order of M,. Iahio> L. cornata coreensis> P. clavigera.