Background: The objective was to explore the value of the CT value difference (?HU) and CT value ratio (CVR) between the hepatic arterial (AP), portal (PP), and delayed phases (DP) to differentiate the small Hepatocellular Carcinoma (SHCC, ≤ 3 cm) from the small Focal nodular hyperplasia (SFNH, ≤ 3 cm). Materials and Methods: All the lesions were confirmed by clinically and/or pathologically and all the patients underwent triple-phase enhanced CT scans. The lesions’ CT values (LCV) and the surrounding normal liver parenchyma (NCV) of the enhancement phases were measured separately, the ?HU and CVR were calculated. Results: The median age and the male/female ratios of the SHCC and SFNH have statistically significant, and the size haven’t statistically significant. The ?HU and CVR of the AP, PP, and DP of the SHCCs and SFNHs were statistically significant, respectively. The area under curve of ?HU and CVR of AP, PP and DP were increased gradually. When the ?HU and CVR of the AP, PP and DP were 105.800HU vs. 1.516, -12.600HU vs. 0.949, -19.750 HU vs. 0.951, obtained the maximum You-den indexes. The corresponding sensitivity and specificity were 80.6 % and 90.1 % vs. 88.90% and 72.1%, 100% and 81.1% vs. 100% and 81.1%, 94.4 % and 96.4% vs. 94.4 % and 96.4%, respectively. Conclusion: The SHCC was highly suggested when ?HU and CVR are no greater than 105.800HU and 1.516, -12.600HU and 0.949, -19.750 HU and 0.951 of the AP, PP, and DP in the middle-aged and elderly male patients, especially in the DP.