Background. Abdominal pain is a symptom of many gastrointestinal diseases (GID). It affects patients’ quality of life and psychoemotional state, regardless of the pathogenetic mechanisms. Dietary nutrition is the most physiological way to prevent and treat pain. Objective. We evaluated the organoleptic properties and safety of the specialized dietary product LEOVIT GASTRO «Oatmeal porridge with herbs and flax seeds» («Dietary porridge») as well as its effect on abdominal pain syndrome and quality of life in patients with GID. Methods. We conducted an open single-center prospective observational parallel-group study. The experimental and control group consisted of 14 and 10 patients with GID, respectively. Only the experimental group got «Dietary porridge». All participants were questioned, examined by a gastroenterologist and internal medicine specialist; underwent complete blood count and biochemical tests, upper gastrointestinal endoscopy, and abdominal ultrasound. Results. 100% of the patients from the experimental group noted the resolution of the dyspeptic symptoms after 180 days taking «Dietary porridge». All patients reported improvement of appetite and normal stool consistency. Pain intensity decreased from 92.8% to 7% in the experimental group. 93% of the patients from the experimental group were in GID remission after 180 days from the start of the study according to endoscopy examination, while in the control group, remission was observed in only 60% of patients. Abdominal ultrasound showed that in 4 patients from the experimental group with gallbladder abnormalities after 180 days of taking «Dietary porridge» the decrease of its size and bile consistency was noted. Conclusion. The safety and clinical efficacy of «Medicinal porridge» in patients with gastrointestinal diseases accompanied by pain has been proven. Against the background of the use of «Medicinal porridge» pain was reduced and the quality of life of patients of the main group improved compared with the comparison group