A close relationship exists between physiological function and biological rhythms in aquatic animals [15]. The organisms have the ability to anticipate the approaching meal and then optimize the digestive and metabolic processes. Several studies have been carried out into this physiological adaption. For example, some enzymatic activities have been observed to increase in the digestive system of fishes prior to the expected intake of the daily food [16–18]. The activities of digestive enzymes in sea cucumber have been extensively studied in relation to the influence of diet composition [4], food processing method [19] and temperature [20]. Nevertheless, the digestive rhythms of sea cucumber have scarcely been investigated