The origin, insertion, gross structure, and the possible action of the muscles of the shoulder joint have been described. The obtained results show differences in the anatomy of the shoulder musculature of wolf and dog. These differences are characterized in wolf by: (1) the muscular and tendinous insertion of the Mm. supraspinatus, deltoideus, teres minor, and coracobrachialis, (2) the wide, long aponeurosis from the entire caudal border of the scapula as the origin of the M. teres minor, (3) the wide insertion of the M. coracobra chialis, and (4) the presence of a well developed M. articularis humeri. The results are illustrated by four diagrams.