Objective To analyze the clinical value of multi-slice CT perfusion technique in the differential diagnosis of liver neoplasm lesions. Methods 40 patients with liver diseases treated in our hospital from May 2013 to May 2015 were taken as the research objects. Pathological examination confirmed that 22 cases were with benign lesions and 18 cases with malignant lesions. 20 cases of healthy persons who received physical examination in the same period were selected as the normal control group. All of them received 320 slice CT perfusion scan. CT perfusion imaging parameters of liver tissues in each group were compared. Results The perfusion parameters of liver cysts were 0. The differences in BF, MTT, HPI and HAP between patients with hepatic hemangioma and liver cancer and the normal control group were statistically significant (P<0.05). BF, BV and PVP of patients with hepatic hemangioma were significantly higher than those of patients with liver cancer (P<0.05). There was significant inhomogeneous high perfusion on liver cancer HAP, with low perfusion in some of the necrotic areas. The perfusion of edges was significantly higher than that of the central necrotic areas; There was significant inhomogeneous low perfusion on PVP, with unconspicuous boundaries between most of the lesions and the surrounding liver parenchyma. There was significant high perfusion in nodular enhanced areas on the upper edge of hepatic hemangioma HAP and low perfusion in early areas without enhancement. In PVP upper perfusion region, there was some low perfusion and low perfusion in early areas without enhancement. Conclusion 320 slice CT perfusion imaging parameters can reflect the blood flow state of liver neoplasm and plays an important role in judging the benign and malignant tumors.