报告１９例以肌无力为首发症状的慢性甲状腺毒性肌病（ＣＴＭ），表现为三种形式：呈对称性，渐进性肢体近端无力伴肩、髋带肌群萎缩１１例，单个肢体无力５例，重叠型肌病３例，出现高代谢征群１３例（６８．４％），无高代谢征群６例（３１．６％），其中４例反而出现厌食、淡漠。并对其临床特点、诊断及发病机理进行了讨论。 Nineteen cases of chronic thyrotoxicosis myopathy (CTM) with myasthenia as the first symptom were reported, showing three forms: symmetry, progressive proximal weakness accompanied by shoulder, atrophy of hip muscle group, and weakness of single limbs. Cases, 3 cases of superimposed myopathy, there were 13 cases of high metabolic syndrome (68.4%), 6 cases of high metabolic syndrome (31.6%), of which 4 cases appeared anorexia, indifference. And its clinical features, diagnosis and pathogenesis were discussed.