Introduction Primary venous aneurysm is a rare, but essential consideration in the diVerential diagnosis of an inguinal and femoral hernia. Methods We report a case of a 43-year-old man who was referred for evaluation and treatment of a femoral hernia. Results The patient presented with a 3-month history of an asymptomatic tumor on his right upper inner thigh. Physical examination noted a non-tender, non-indurated tumor. Conclusion Surgical exploration demonstrated a primary venous aneurysm of the proximal saphenous vein.