Popliteal artery cystic adventitial disease (PACAD) is an uncommon nonatherosclerotic arterial occlusive disease. We describe three cases of PACAD that spontaneously remitted. The three patients included a 56-year-old man, 34-year-old man, and 72-year-old man who presented at our hospital with intermittent claudication of the extremities. Diagnostic imaging, such as enhanced computed tomography (CT) or magnetic resonance imaging (MRI), showed scimitar-shaped cystic lesions with severe narrowing or obstruction of the affected popliteal artery. In two of the cases, enhanced CT revealed that multilocular cysts of the arterial wall had connected to the knee joint. Therefore, the patients were diagnosed with PACAD and scheduled for surgical repair. Subsequently, claudication or calf pain improved awhile. The intervals from onset to remission of the symptoms were three months, 34 days, and 13 days, respectively. Examinations showed normal distal pulses; duplex or contrast-enhanced CT revealed that the diameters of the cystic lesions were decreased and that the blood flow in the popliteal arteries was normalized. Accordingly, the operations were cancelled, patients underwent conservative therapies, and they were followed up as outpatients. Exacerbation after remission of calf pain was observed in one case, the 72-year-old man. One week later, however, this symptom due to leg ischemia improved under conservative treatment. The three patients have remained asymptomatic with normal ankle pressure up until the present. Although spontaneous regression of PACAD is rare, our cases demonstrated the possibility of permanent remission of PACAD. There may be justified conservative therapies for non-limb-threatening cases of PACAD before surgery.