Although a popliteal cyst is most commonly identified as an asymptomatic mass occurring just below the popliteal fossa, the fluid may further extravasate into a deep compartment, causing compression with symptoms of local pain and tenderness. When the popliteal vein is compressed by a popliteal cyst, it may develop the symptom simulating the deep vein thrombosis, when the popliteal artery is compressed, it may develop the symptom simulating the ischemic pain and intermittent claudication. It is unusual for popliteal cysts to involve a nerve. When such does occur, it usually involves the tibial nerve, very rarely the peroneal nerve. It is important to diagnose a popliteal cyst early and to differentiate it from a ganglionic cyst, thrombophlebitis or a popliteal aneurysm, to effect optimal therapy and to obviate a potential neuropathy. We are now reporting a case of a thirty four-year-old male who had a popliteal cyst causing tibial nerve compression.