Bariatric surgery leads to significant weight loss and improvement of obesity-related diseases. Despite the benefits of these operations, deficiency of vitamins and other micronutrients is common. Therefore, the aim of this research was to try to produce a nutritional product from fermented milk fortified with some natural additives to meet the nutritional needs of bariatric surgery patients. Three treatments of fermented cow's milk were manufactured, the first treatment was lactose-free fermented cow's milk fortified with vitamin D and sweetened with 10% date molasses (control treatment), the second treatment was the fermented milk in the first treatment but cow's milk was replaced with 25% barley milk, while the third treatment was the fermented milk in the first treatment but cow's milk was replaced with 50% barley milk. The chemical, sensory and bacteriological properties of the resulting bio-fermented milk treatments were estimated, as well as the contents of the most important nutritional elements that are deficient after bariatric surgery, such as vitamins A, D, K, E, B1, B12, iron, calcium, zinc, copper and selenium. As compared with the daily needs, and the amount that the prepared meal weighing 100 grams contributes to the management of common micronutrient deficiencies after bariatric surgery. The results showed that all the treatments of the resulting fermented milk were sensory acceptable to the judges and had a high nutritional value in terms of their content of total solids, protein, dietary fiber and carbohydrates, in addition to their high content of nutrients that are deficient after bariatric surgery such as vitamins A, D, K, E, B1, B12, iron, calcium, zinc, copper and selenium. The third treatment containing 50% barley milk gave the best results compared to the rest of the treatments. When compared to the daily nutritional needs recommended for healthy people, it was found that consuming 200 grams of it daily provides almost most of the nutritional needs necessary for healthy individuals. Therefore, this product may be suitable for feeding bariatric surgery patients after 12 months of surgery and that it meets most of their daily nutritional needs.