Bariatric and metabolic surgery BMS is an important method for treating obesity and metabolic diseases yet it is frequently associated with postoperative complications. Anemia is a common complication with its incidence influenced by factors such as country surgical technique and follow-up duration. The primary cause is impaired nutrient absorption post-surgery leading to deficiencies in iron vitamin B12 folic acid and copper. Additionally peptic ulcers and menstrual blood loss are significant contributing factors. Conditions such as refractory iron deficiency anemia thalassemia and Helicobacter pylori infection may further elevate the risk of postoperative anemia. The treatment of iron deficiency anemia after BMS should adopt a stepwise management approach. First dietary modification to increase nutrient-rich food intake is recommended. If ineffective oral supplementation should be initiated. For patients with malabsorption or severe anemia intravenous supplementation can rapidly replenish nutrient reserves. Clinically individualized plans should be formulated in combination with the patient's surgical method nutritional status and comorbidities. Concurrently screening and addressing specific underlying causes are crucial to reduce the incidence of postoperative anemia and optimize treatment outcomes.