Clinical data of 129 young pafienm with lung cancer were analyzed retrospectively.Adenocarcinoma was the main pathologic type of lung cancer(n=62,48.1%),followed by undifferentiated small cell carcinoma(n=35,27.1%),squamous carcinoma(n=20,15.5%).Forty four cases were misdiagnosed at first consultation with a misdiagnosis rate of 34.1%.To avoid misdiagnosis seems to be the key issue for improvement of prognosis in young patients with lung cancer.