Neoplasms of the small bowel are relatively rare, with less than 5% occurrence among other GI cases. Primary adenocarcinoma, an aggressive sub-type of small bowel cancers, usually presents with vague blood loss and abdominal pain symptoms, causing a delayed diagnosis at an advanced stage of the disease and a poor prognosis. The preferable treatment of choice is surgical resection with chemotherapy, which has shown to have survival benefits. Here we present a case of a 66-year-old male patient with persistent iron deficiency anemia requiring multiple blood transfusions and an unexplained weight loss. A series of diagnostic tests, including upper and lower GI endoscopy, Tc-99 RBC scintigraphy, barium follow-through, CT scans, bone marrow biopsy, esophagogastroduodenoscopy and colonoscopy were inconclusive. He was later diagnosed with a small bowel adenocarcinoma on exploratory laparotomy and surgically treated. Adjuvant chemotherapy was also started. Our case report highlights the course of SBA presenting in an unusual way which was challenging to diagnose with the standard investigations to help physicians/surgeons suspect it at an early stage in the future. This may save patients and help avoid delayed diagnosis or misdiagnosis, especially in patients with an unusual presentation like our patient who presented only with iron deficiency anemia.