In our study, we found that the levels of PLK1 were higher in in lung squamous cell carcinoma tissues compared with lung adenocarcinoma tissues, and PLK1 high expression was the aggressive progression and poor prognosis in lung squamous cell carcinoma patients, which implied that PLK inhibitors may have surprising clinical efficacy in lung squamous cell carcinoma patients. This evidence concerns the gene PLK1 and squamous cell lung carcinoma.