Left-sided inferior vena cava (IVC) is the second most common anatomical anomaly of the IVC after duplication. Herein, we present two cases of left-sided IVC, diagnosed during organ retrieval procedure. In a young brain-dead man, a single left-sided IVC was observed; it originated from iliac confluence in the left side of the aorta and extended throughout the abdomen. There was no retrohepatic IVC in the patient; hepatic veins drained directly into the right atrium. The second case was a brain-dead young woman with a left-sided IVC originated from iliac confluence to the kidney level; then, the IVC crossed anterior to the abdominal aorta to join a normally positioned retrohepatic IVC. In cases of retroperitoneal surgeries, IVC anomalies should be considered during preoperative imaging studies, because they may be misdiagnosed as para-aortic lymphadenopathy, tumor or dilated gonadal vein that may result in iatrogenic damage during surgery.