Objective To investigate the research value of spiral CT on clinical diagnosis of peripheral lung cancer. Methods 65 cases with peripheral lung cancer in our hospital from 2008 to July 2015 were selected and retrospectively analyzed. CT imaging of 65 patients were analyzed by 3 diagnostician, data were analyzed by professional software. Results In CT scan, pleural indentation, vascularnotch sign, mediastinal lymph node metastasis of 65 patients had obvious difference on pathological examination; In statistical data of poorlydifferentiated, moderately-differentiated, highly-differentiated, pleural indentation, vascularnotch sign, mediastinal lymph node metastasis had obvious difference, the difference was statistically significant. Conclusion Pleural indentation, vascularnotch sign, mediastinal lymph node metastasis have obvious difference on pathological examination and need further analysis. 16-slice spiral CT has certain research value on clinical diagnosis of peripheral lung cancer.