All authors have no conflict of interest to declareNo funding sourcesPatients signed informed consent regarding publishing their data and photographsAbstract :The occurrence of superficial vein aneurysms is uncommon. This report includes three lower extremity cases: a 38-year-old man with a Great saphenous vein aneurysm mimicking an inguinal hernia, a 40-year-old woman with a Small saphenous vein aneurysm at the back of her knee, and a 35-year-old smoker man with a dorsal foot mass confirmed as a medial marginal vein aneurysm on doplex sonography. All patients denied any prior trauma. All patients denied a history of trauma. and all of them had no medical history. all aneurysms were excised and their postoperative evaluation were uneventful. This article may increase awareness and encourage surgeons and radiologists to consider venous aneurysm as a differential diagnosis among all lower limb lesions, from the groin to the foot.Key Words : Lower Extremity, Aneurysm, Veins, Venous Thrombosis, saphenous veinIntroduction :The superficial venous system is a complicated web of collecting veins and thicker-walled truncal veins that run between the skin and the muscle fascia. They serve as large-capacitance reservoirs and are responsible for venous drainage from the skin and subcutaneous tissue(1). Superficial venous aneurysms can be misinterpreted as several soft tissue tumors and hernias dependent on the location of the aneurysm. In case of the lower extremity, distinguishing between varicose veins and venous aneurysms is also important. Because of their distinct pathophysiology, the management strategies for these two clinical entities differ(2). Although uncommon, thrombosis and concomitant embolism have been reported in association with vein aneurysms (3-5). This paper summarizes three rare cases of superficial vein aneurysms in diverse locations of the lower limb, with their presentation, chief complaint, and management. all patients presented to the Shohadaye Tajrish hospital’s outpatient clinic.Case 1:A 38-year-old man arrived with a compressible mass at the groin region (figure 1). he never had any episodes of pain and denied trauma to the area. He first noticed swelling about a year ago, it varied with position and was easily repressed by hand pressure (Figure2). The patient was a smoker with no history of DVT, malignancy, or other complications. Physical examination revealed a 4 × 5 cm2soft mass with no discomfort. His left leg had a moderate amount of varicosities. Doppler sonography verified the diagnosis. A Right oblique inguinal incision was performed under spinal anesthesia, the aneurysm of great saphenous vein (GSV) was excised, distal and proximal veins were ligated.Case 2:A 40-year-old woman presented with a painless mass at the back of her knee during the past 6 months. There are no additional comorbidities, and she has never smoked. There was no history of leg trauma, DVT, edema. On exam, the patient had an erythematous non-pulsatile, 4 × 1 cm2 mass that was non-tender to palpation. Doppler sonography confirmed the diagnosis. In the operating room, the aneurysm was excised and the proximal and distal continuation of the small saphenous vein (SSV) were ligated(Figure 3). The patient tolerated the procedure well and was discharged home on postoperative day 1Case 3:A 45-year-old man with a complaint of a mass on the medial of his right foot that made him uncomfortable when he wore shoes. He had no other significant medical or smoking history. On physical examination, a soft lesion measuring 3 × 4 cm2 was found on the top of the foot (Figure 4). The diagnosis was confirmed by Doppler ultrasound. Ligation and simple excision was the utilized technique in the surgery. The patient was operated under local anesthesia with lidocaine solution. Via longitudinal skin incision, the sac of aneurysm was visualized and has been dissected from the surrounding tissues