Objective To discusses the feasibility of CT scanning of low-x and low iodine content in early lung cancer. Methods Collected January 2014 to December 2016, the chest CT scan was performed and 96 patients were screened for lung cancer. Grouping all of the patients using completely randomly divided into routine dose group (regular doses of radiation and dosage of contrast agent 1.5 ml/Kg) and double low dose group (low doses of radiation and dosage of contrast agent 1.0 ml/Kg), contrast medium concentration of 270mg/100 ml. Comparison between different groups of diagnosis, CT value, signalto-noise ratio (SNR), contrast to noise ratio (CNR), image noise standard deviation (SD), score values, as well as imaging dose and dose volume CT dose index, the length of the product, effective dose. Results Two experimental diagnosis, CT value, signal-to-noise ratio (SNR), contrast to noise ratio (CNR), image noise standard deviation (SD), score values between no statistical difference (P>0.05), angiography was statistically difference between dose and effective dose (t=13.451, P><0.05, t=0.05, P<0.05). Conclusion Double low-dose CT scans and iterative reconstruction techniques were able to obtain satisfactory early lung cancer scans, which had significant clinical implications for early lung cancer screening.