Correct diagnosis of the tendon pathology is a basis for treatment and prognosis of the disease. Today there are practically two imaging modalities widely used for the Achilles tendon diagnosis: US and MRI. Ultrasound is superior to MR in the tendon assessment. It not only allows to diagnose early degenerative, inflammatory disease, both partial and total tears and tendon-related pathologies but also gives us the opportunity to do dynamic examination and perform noninvasive assessment of the perfusion within and around the tendon. Those two features, unavailable with MR allow us to differentiate degenerative and inflammatory processes as well as partial and total tears.