Enteral nutrition through filiform naso-duodenal or naso-jejunal tubes with homogeneous low molecular nutritional solutions has a rather important place in therapy of different conditions; endoscopy can help to introduce these tubes into the intestinal tract in the following situations: A leak in the upper gastrointestinal tract, which may occur after surgical resections of the esophagus or stomach, or which may occur in rare cases after bouginage or after diagnostic procedures can be passed by with an ultrathin tube until it is healed of. Patients with stenotic lesions of the esophagus or the cardia, which can not be treated by surgery or conservative procedures like pertubation and dilation can be fed enterally if it is possible to move the tube beyond the stenosis. Patients with neurogenic swallowing dysfunction of different origine can be fed during long periods of time through such filiform naso-enteral tubes successfully and reach a perfect nutritional state. In acute treatment of Crohn's disease and other inflammatory intestinal diseases enteral nutrition through tubes is an essential therapeutic procedure.