目的　分析支气管肺癌致抗利尿激素分泌不当综合征 (SIADH)的临床及影像学表现。方法　回顾性分析 11例经病理证实的肺癌合并SIADH患者的临床、胸片、CT和MRI表现。结果　具有异位抗利尿激素 (ADH)分泌功能的肺肿瘤为小细胞肺癌和支气管类癌 ,大部分患者临床最初表现为顽固性低钠血症 ,误诊漏诊率高。结论　SIADH临床少见 ,对不明原因的顽固性低钠血症患者 ,应想到肺肿瘤的可能 ,影像学检查是必要的 Objective To analyze the clinical and imaging findings of syndrome of inappropriate secretion of antidiuretic hormone (SIADH) in bronchial lung cancer. Methods The clinical manifestations, chest X-ray, CT and MRI findings of 11 pathologically confirmed lung cancer patients with SIADH were retrospectively analyzed. Results Lung tumors with ectopic anti-diuretic hormone (ADH) secretion were small cell lung cancer and bronchial carcinoid. Most of the patients initially presented with intractable hyponatremia and high misdiagnosis rate. Conclusions SIADH is clinically rare. Patients with refractory hyponatremia of unknown cause should be reminded of the possibility of lung cancer. Radiographic examination is necessary