1. 1. The carbohydrase activities in the digestive tract of the edible snail Helix lucorum (juveniles and adults) were studied. 2. 2. The main digestion of carbohydrates takes place in the oesophagus, the crop, the stomach, the intestine and the digestive gland. 3. 3. Helix lucorum was able to degrade the majority of the substrates tested (oligosaccharides, synthetic oligosaccharides and polysaccharides). 4. 4. The respective enzymatic activities varied according to the physiological state of the animals examined (hibernated, starved and fed animals). 5. 5. Starch, xylan, lichenine and saccharose were the least hydrolysed substrates while the full enzyme set responsible for the degradation of native cellulose seemed to exist in the digestive tract of H. lucorum. 6. 6. There follows a discussion on the exogenous or/and endogenous origin of the enzymes.