The digestive system of the earthworm consists of the alimentary canal and the digestive glands. The alimentary canal runs as a straight tube throughout the length of the body from the mouth to anus. The mouth opens into the buccal cavity which occupies the 1 and 2 segments.

The buccal cavity leads into a thick muscular pharynx,which occupies the 3 and 4 segments and is surrounded by the pharyngeal glands. A small narrow tube, oesophagus lies in the 5 segment and continues into a muscular gizzard in the 6th segment. The gizzard helps in the grinding of soit particles and decaying leaves.

Intestine starts from the 7^th segment and continues till the last segment. The dorsal wall of the intestine is folded into the cavity as the typhlosole. This fold contains blood vessels and increases the absorptive area of the intestine. The inner epithehum consists of columnar cells and glandular cells. The alimentary canal opens to the exterior through the anus. The ingested organic rich soil passes through the digestive tract where digestive enzymes breakdown complex food into smaller absorbable units.

The simpler molecules are absorbed through the intestinal membrane and are utilized. The undigested particles along with earth are passed out through the anus, as worm castings or vermicasts. The pharyngeal or salivary gland cells and the glandular cells of the intestine are supposed to be the digestive glands which secrete digestive enzymes for digestion of food.