Background Spigelian hernia is an uncommon presentation of abdominal hernias with 0.1-2%. We report a case of a large strangulated Spigelian hernia, an uncommon presentation of abdominal hernias, and its management in a health facility in Central Uganda. Case Presentation A 76-year-old female presented with a 2-day history of colicky abdominal pain, bilious vomiting, and abdominal distension. On abdominal ultrasound scan, an abdominal wall defect measuring 4.45 cm with herniated bowel loops in the left anterior abdominal region with mild fluid collection in the hernia sac was seen. Conservative management for intestinal obstruction which included putting the patient on nil per os, NG tube decompression, and soapy enema was instituted, and surgery was done on the second day of admission. Intraoperatively, using a Rutherford-Morrison incision, we found a large defect at the Spigelian aponeurosis, with an inflamed sac protruding. The Spigelian hernia was repaired with a mesh under layers. The patient recovered uneventfully and was discharged 10 days after surgery. Conclusion Clinicians and especially general surgeons might be aware of this rare condition in most of the anterior abdominal swellings. Strangulation is the commonest complication of Spigelian hernia, and surgical management remains the mainstay of its treatment.