Background: Bariatric surgery has a major role in treatment of obesity for patients with a history of unsuccessful trials to lose weight, as it gives the most successful results in achieving goals of weight reduction. Aim and objectives: The aim of this study was prevention of nutritional deficiencies through assessment of nutritional status among bariatric surgery patients. Methods: A case control study was conducted on 3 groups (32 participants in each group), Bariatric surgery individuals (12-18 months after surgery), Obese on diet individuals and Obese without diet individuals at Zagazig city from the beginning of Dec. 2019 to the end of Sep. 2020. Nutritional status was assessed using SGA Questionnaire. Results: The mean age was 32.41 ± 7.51 years. Females were about 3/4 of all groups. Most of the studied bariatric surgery group had Gasterectomy surgery and Gastric Bypass (68.8 % and 15.6 %) respectively. 75% of bariatric surgery group were severely malnourished while (62.5%) and (75%) of obese with diet and obese without diet groups respectively were moderately malnourished. Conclusion: Nutritional deficiencies are very common after bariatric surgeries more related to sleeve gastrectomy than balloon procedures.