Fibromuscular dysplasia (FMD) is a nonatherosclerotic, noninflammatory vascular disease that mostly affects the renal and internal carotid arteries, rarely complicating lower limbs. We report a case of FMD complicating critical limb ischemia due to the obstruction of below the knee arteries, diagnosed and treated with the support of skin perfusion pressure (SPP) measurement. Initial angiogram revealed the anterior tibial artery (ATA) was subtotally occluded showing a "strings of beads" pattern, which is typical of the arteries affected by FMD. SPP guided endovascular therapy was successful for ATA lesions. Intractable rest pain subsequently disappeared and the ulcer was completely healed without amputation.