INTRODUCTION: Blue rubber bleb nevus syndrome (BRBNS) is a rare vascular anomaly syndrome consisting of multifocal venous malformations. It frequently presents a diagnostic and therapeutic challenge in patients with gastrointestinal involvement. CASE DESCRIPTION/METHODS: A 55-year-old male presented with symptomatic anemia. Physical examination showed paleness and tachycardia. Laboratory studies showed hemoglobin 5.8 g/dL with normal white cell count. Peripheral blood smear showed microcytosis and hypochromia. Coagulation studies and routine biochemistry values were normal. He received packed-red cells and iron supplementation. He underwent upper and lower endoscopies. Colonoscopy showed multiple scattered venous blebs throughout the colon. They ranged in size from 2 mm to 8 mm. None of these blebs were actively bleeding. These lesions were not amenable to endoscopic treatment. Treatment was conservative with PPIs, blood transfusions and iron replacement. DISCUSSION: BRBNS is a rare, multifocal vascular malformation. According to a PubMed search, a total of around 200 cases are reported to date. Although data is sparse, it more commonly occurs in the skin (93%) and gastrointestinal tract (76%). A thorough physical examination and diagnostic workup for any symptomatic site should be performed in all suspected cases. Gastrointestinal involvement is a great masquerader as these patients experience severe anemia for years without diagnosis. In these patients, bleeding from the gastrointestinal tract is the most important clinical feature of BRBNS owing to the risk of excessive bleeding. Antiangiogenic agents such as interferon, corticosteroids, or sirolimus may be an effective treatment option for gastrointestinal BRBNS. In future, more cases should be reported in order to understand the etiological factors and treatment approaches.