Objective To explore the dual-source CT dual-energy parameters and their value in differential diagnosis value of different pathological types of lung cancer. Methods A total of 86 cases of newly diagnosed lung cancer patients admitted to our hospital during November 2014-November 2016 were examined with dual-source CT dual -energy imaging, including 52 cases of adenocarcinomas and 34 cases of squamous cell carcinomas. After scanning, the CT net added values and time-density curve of patients with squamous cell carcinoma and adenocarcinoma in different phases were analyzed and compared. Results The time to peak of lung adenocarcinoma was (21.04±0.23)s, while of lung squamous cell carcinoma was (23.12±0.3)s (P<0.05). The CT net added values of enhanced scan in different phases in adenocarcinoma group to peak, 60s and 100s after reaching the peak were significantly higher than those of the squamous cell carcinoma group (P<0.05). There was no significant difference between the two groups at 40s after reaching the peak (P>0.05). The CT net added value of enhanced scan for lung adenocarcinoma was the lowest in aortic peak, it increased significantlyat the 40thsecond (P<0.05) and increased gradually over time. The CT net added value of squamous cell carcinoma was the lowest in aortic peak(P<0.05), it was the highest at the 40thsecond, slightly decreased at the 40th-60thsecond, and it was in platform stage in 60th100thsecond. Conclusion The time-density curve of adenocarcinoma CT net added value shows a gradually increasing trend while that of squamous cell carcinoma shows an firstly increasing, then decreasing and finally flat trend. Dual-source CT dual energy imaging can provide certain references for pathological diagnosis of adenocarcinoma and squamous cell carcinoma.