Objective To analyze the value of multi-slice spiral CT in the screening of high-risk lung cancer and its imaging findings. Methods 120 patients with high-risk lung cancer who received health physical examination in our hospital from January 2012 to June 2014 were taken as the research objects. All the subjects underwent multislice spiral CT examination, including routine scan and low-dose scan. The lung lobe structure and pulmonary nodules displayed by CT scan were observed and recorded. Results The differences in displaying lung lobe structure and number of pulmonary nodules between routine dose and low-dose multislice spiral CT were not statistically significant (P>0.05). 33 small pulmonary nodules were detected by multi-slice spiral CT, including 28 benign and 1 malignant; Surgical therapy was performed and pathological examination was used to confirm. 3 patients needed to be followed up and 2 of them were reexamined in 3 months, showing enlargement of nodules. Through surgical treatment and pathological examination, they were confirmed as early lung cancer. 1 case was reexamined in 6 months. The size changes of the nodules were not obvious. 18 months later, the reeaxmination showed spot-like calcification in central nodules, determined as benign nodules. Conclusion Multi-slice spiral CT can clearly display the lobe structures and the number of pulmonary nodules, which is of great significance in the early screening of lung cancer in high risk population. Low-dose CT screening is suggested.