Abstract: Primary sarcomatoid carcinoma of the lung is a rare malignancy.This study was to investigate its clinical characteristics, diagnosis and prognosis. Methods The data of patients with pulmonary sarcomatoid carcinoma between Jan. 2001 and Dec. 2006 were reviewed. The survival rates was calculated with Kaplan-Meier method and compared with Log-rank method, Cox proportional hazards model was used for multivariate analysis. Results Totally 22 patients were eligible, including 16 male and 6 female, most of whom had smoking history. The median age was 63. The 5-year survival rate was 26.5% with a median overall survival of 0.96 year. The 5-year survival rates of patients in stage Ⅰ,Ⅱand Ⅲ were 60.0%,0 and 11.1%(P=0.0014),respectively. Only T stage and necrosis were independent poor prognostic factors( P＜0.05). Conclusion Most of patients with lung sarcomatoid carcinoma are older males, who has heavy smoking history. Early postoperative distant metastasis is the first reason caused death. The prognosis of the patients with pT₃ and necrosis is poor.