Relationship among thyroid dysfunction and musculoskeletal symptoms has been known for years. Autoimmunic thyroiditis is the most common cause of hypothyrosis. A patient who suffered from myopathy secondary to autoimmunic thyroiditis and hypothyrosis is described in this article. Attention has been drawn to proximal muscle weakness and general fatigue which is common in such cases. Significant elevation of muscle enzymes is typical. Usually no specific signs can be found on muscle biopsy. Much efforts should be put to distinguish myopathy secondary to hypothyrosis from polymyalgia rheumatica, polymyositis or myopathies caused by other diseases. Similar data of literature are reviewed in the article.