Arterial adventitial cystic disease is an uncommon type of non-atherosclerotic peripheral vessel disease. Most cases of arterial adventitial cystic disease occur in the popliteal arteries; however, fewer cases have been reported in the femoral arteries. A 59-year-old male patient visited the hospital with a complaint of a swelling on the lower extremity that had begun two months earlier. Suspecting deep vein thrombosis based on a physical examination and ultrasonography from another hospital, tests were performed. Magnetic resonance imaging (MRI) was performed for exact diagnosis because venous adventitial cystic disease was suspected by computed tomography venography. The MRI indicated venous adventitial cystic disease as well. Thus, a cystic mass excision was performed. In the end, a cystic mass compressing the common femoral vein that originated from the common femoral artery was diagnosed based on the macroscopic findings. This case is reported because blood circulation in the vein was impeded due to arterial adventitial cystic disease, and the symptoms improved after the cystic mass excision and polytetrafluoroethylene roofing angioplasty.