The present case report regards the incidental finding of right popliteal vessels entrapment by a variant accessory belly of the medial head of gastrocnemius. The accessory head of gastrocnemius took origin from the popliteal surface of the femur and joined the medial head. The popliteal vessels passed between the medial and the accessory head of the gastrocnemius. The accessory head was quite large and was supplied by a branch of tibial nerve. Popliteal vessels compression usually leads to a condition called popliteal vascular entrapment syndrome which is a rare clinical entity, predominantly in young adults. This anomaly might cause intermittent claudication, aneurysmal dilatation, thromboembolism and eventually limb-threatening ischemia. Early recognition and diagnosis is important to minimize surgical treatment and avoid vascular reconstruction. Knowledge about the rare anatomical variants of popliteal vessels is helpful for correct diagnosis and planning of treatment.