In 110 patients with peptic ulcer aged from 16 to 25 years and in 15 healthy youths the secretary function of the stomach was studied by using fractional tubage with 300 ml of a 7% dry cabbage water as a stimulator. The secretory function was assessed according to the titrated acidity, pepsin and gastricsin data. Investigations were conducted repeatedly, viz. On admission to the clinic, following treatment with No 1 diets with an elevated protein and fats content (120--130 g) and also 8--10 months after discharge from the inpatient department. The dietotherapy (carried on for 42--45 days) did not produce any substantial normalization of the secretory gastric function, and this despite the improvement in the general condition of the patients and scarring of the ulcerous defect. A well marked tendency toward normal secretion of hydrochloric acid and proteolytic enzymes was seen to take place late after institutional dietetic treatment (in 8--10 months), provided the patients kept strictly to the prescribed dietary regimen. The normalization of the hourly HCl yield and the fall of the pepsin and gastricsin activity with the disease in the phase of remission (in 8--10 month time) concerned the first phase of secretion exclusively.