A rare cause of occlusive vascular disease is the "Popliteal Artery Entrapment Syndrome." The most common cause of this problem is abnormal position of the popliteal artery caused by abnormal migration of the medial head of the gastrocnemius. An acquired form can occur because of tunneling defects by inadvertent placement of venous bypass graft medial to the medial head of the gastrocnemius muscle. We present 2 cases of iatrogenic entrapment of the femoropopliteal bypass graft. Investigations revealed compression of the graft with extension of the knee. Both cases were treated surgically. Intraoperatively there was evidence of compression of the graft between the tendons of the semitendinosus and the gracilis muscles and the medial head of the gastrocnemius muscle. Treatment involved division of the medial head of the gastrocnemius in 1 patient, and in the other, the tendons of gracilis and semitendinosus were divided. No compression of the graft was noted postoperatively by noninvasive test. No significant mobility issues caused by the division of muscle or the tendons were present in the postoperative period.