It is difficult to palpate the supraspinatus muscle since it is difficult to determine their anatomic location superficially. Magnetic resonance elastography (MRE) can measure tissue stiffness quantitatively only if vibrations reach these tissues. To vibrate the tissues efficiently, it is necessary to determine the best excitation location. We investigated the excitation location suitable for MRE of the supraspinatus muscle. When the excitation location was placed on the trapezius muscle, the wave images represented clear wave propagation compared with those on the head of humerus. Therefore, optimal excitation location may be the trapezius muscle in the MRE of the supraspinatus muscle.